PFIS INTERFACE CONTROL DOCUMENT cdr/c… · PFIS ICD Note: 1) The system specification requires that no subsystem in the optical path should: • have a surface temperature of more

PFIS ICD

SALT FOUNDATION

PFIS INTERFACE CONTROLDOCUMENT

PFIS ICD

1 SCOPEThis document describes the interface between PFIS the various subsystemsof SALT. The subsystems are:

a) Tracker rotation stageb) Guidance Probesc) SALTICAM (slit image)d) Igloos behind Primary Mirrore) Cooler Boxes on TOP HEXf) Cooler boxes for electronics on PFISg) Computer Roomh) Control Roomi) Glycol and air Supplyj) Electrical Power

PFIS ICD

2 INTERFACES2.1 PFIS

The PFIS can be divided into the following major components that will have interfaces withthe Payload Structure and or other parts of SALT:

• Cooler Boxes on PFIS, enclosing all PFIS electronics• Structure (Which will mount onto Tracker Rotation Stage)• Cryocooler (mounted in a cooler box behind the Primary Mirror-called the Igloo)• PFIS computer (Located in control Room)• PFIS Man Machine Interface (MMI) display and controls, called from any computer on

the network

Note: A cryocooler will also be required for the commissioning instrument. If possible both thePFIS and Commissioning instrument can use the same one.

The following schematic diagram shows the location of the various PFIS subsystems andinterfaces. Interfaces are numbered and will be discussed subsequently (i indicates internaland e external interfaces)

FACILITY

Control Room

Computer Room

Electrical Room

PFIS MMI Display &Controls

PFIS Computer

TCS Server

Normal, UPS PowerIsolatorsElectronics

Telescope Chamber

Telescope Structure

Igloo(PM):Cryocooler

Tracker Rotation Stage:

Utilities Building

GlycolCompressed Air

1i

1e

2i

2e

3e

4e5e

3i

Cooler Boxes(TOP HEX)

Cooler Boxes(PFIS)

PFIS Structure Guidance Probe

4i

5i

SALTICAM

6e

7e

PFIS ICD

The subsequent sections will describe the various external interfaces of PFIS.

2.1.1 PFIS Computer <-> TCS Server (1e)

2.1.1.1 Electricala) Network connection

1) Connectors2) Electrical wiring details3) Distance

b) Precise Time Signal(TBC)1) Connectors2) Electrical wiring details3) Distance

2.1.1.2 Dataa) Health status information (TBD)b) Commands for slit alignment (TBD)c) RA and DEC (TBC)(DATA ICD ???)

2.1.2 PFIS <-> Electrical Power (2e)a) Power Supply

NOTE: SALT to Supply Power up to Isolator Switches, from there it is theresponsibility of PFISb) C bl R t t TOP HEX d I l b hi d P i Mi

Essential Power(SALT) 220VAC, 20A,single phase

UPS Power(SALT) 220VAC, 15A,single phase

UPS CCD(SALT) 220VAC, 10A,single phase

Igloo behind Primary Mirror (D)

PFIS PowerDistribution Panel Isolator Switch 1

PFIS PowerSupply

PFIS PowerSwitch

Cryocooler

Cooler Box atTOP HEX

Isolator Switch 2 PFIS PowerDistribution Panel

PFIS PowerSupplies

PFIS PowerSwitches

Etalon Controller

Cooler Box on PFIS-PXI Chassis-PXI power supply-Stepper power supply-SDSU power supply-SDSU Array Controller-CCD Ion pump Contr-CCD Vac Gauge Contr-Star Tracker Base

Isolator Switch 3

Isolator Switch 4

PFIS ICD

DistanceMarker

Distance[m]

S1 8.674S2 2.676S3 8.674S4 4.209S5 1.340S6 2.282S7 12.986

c) Cable Routes from TOP HEX to PFIS

Total length is approximately 20m, the exact routing still to be finalised.

2.1.3 PFIS <-> Glycol and Air Supply (3e)

a) SALT to supply glycol to cooler boxes and Igloo.b) Clean air supply: Outlet supplied by SALT on Payload

1) Flow rate 3l/min2) Pressure 6bar (+-1)

c) Normal air supply: Outlet supplied by SALT on Payload1) Flow rate 3l/min2) Pressure 6bar (+-1)

d) Layout and connector drawings: TBD

e) Maximum Cooling Capacity Available to PFIS: 1.3kW

Payload Igloos (D,E)

D E

S1

S2

S3

S4

S5

S6

S7

PFIS ICD

Note:1) The system specification requires that no subsystem in the optical path should:

• have a surface temperature of more than 8degC above ambient.• have forced-air cooling which is exhausted into ambient• dissipate more than 4Watts continuously to ambient, if so the item must be

housed within an enclosure from which heat will be removed by the Glycolsystem

2) The system specification requires that no subsystem outside the optical pathshould:

• have a surface temperature of more than 8degC above ambient.• have forced-air cooling which is exhausted into ambient• dissipate more than 6.5Watts continuously to ambient, if so the item must be

housed within an enclosure from which heat will be removed by the Glycolsystem

2.1.4 PFIS Structure <-> Tracker Rotation Stage – 4e

2.1.4.1 Physical

PFIS ICD: 03/03/11

b) PFIS – Orientation relative to SALTICAMThe picture below shows the telescope configuration in VI mode. The coordinate systemis centred on the PFIS focal plane. Zenith is in the negative Z-direction. SALTICAM willbe mounted in the YZ plane (below the star tracker head in the figure below), with thePFIS slit coincident with Y. The fixed mounting point of PFIS and the structure carryingSALTICAM will be on Y. +Y is at a nominal elevation (relative to local horizon) of 37°.

2.1.4.2 Constraintsa) Mass of PFIS < 375kg (including Infra Red Beam)b) Volume above prime focus:

(i) Diameter : 3.0m(ii) Height : 1.5m

c) Centre of Gravity in a cubic volume of less than 10x10x10cm , centred less than65cm above the focal plane.

d) Structural stability of mechanical mounting points (under all loading andenvironmental conditions):

(i) Stability of mounting points relative to one another, in z-direction, shouldbe less than 10 microns.

(ii) Global tilts relative to optical axis shall be less than 100 arc seconds(iii) Movement in focus direction shall be less than 100 microns

e) Accessibility(i) Slit mask replacement once a week(ii) Filter wheel replacement once a month

f) Adjustability: The PFIS structure shall provide mechanisms to adjust alignment withthe focal plane and optical axis. This means 5 degrees of freedom adjustability, x, y,z, tip and tilt. The ranges to provide for is as follows:

(iii) X, Y >= 3mm(iv) Z >= 2mm(v) Tip and Tilt >= 0.3 degrees

Star TrackerHead

Star TrackerElectronics

PFIS ICD: 03/03/11

2.1.5 PFIS Structure <-> Guidance Probe – 5e

2.1.5.1 Physical

Note: The figure below is about to be changed within the next month aftercompletion of the proto-type. Some of the dimensions are expected to changequite a bit.

PFIS SUPPORT

FOCAL PLANE

SCIENCE

GUIDANCE PROBE

2.1.6 TOP HEX Cooler Box <-> TOP HEX – 6e

2.1.6.1 Physicala) Dimensions of packaging space required by PFIS: 480 x 380 x 270mmb) Cooling Capacity required: TBDc) Interface between Cooler Box and electronics Frame: TBDd) The figure below depicts the layout on the top hex.

PFIS ICD: 03/03/11

Interfaces for RRS Proposed Rail Beam Ass.

Faried

22/10/02

Front View

Manifold (Air) Pfis

Tracker Box-1.6m wide

Manifold(Glycol)

Power & DataPlugs

Gap for cable access

Side View

Space for cables

Items to go on top hex 1. Electrical DB box (220v + UPS)2. Glycol manifold (fluid return)3. Air manifold (normal + clean)4. Pfis Electronics enclosures5. Tracker Electronics Enclosures6. other ? - Payload ? - Estop ?

1. Gable routing under the beam2. Leave space at the ends for cable3. Transition from uprights to horizontal4. DB box can be placed around the side of the beam if space is a problem.

General

1. Sizes of manifolds2. As build clearance between catwalk and top hex.3. Means of filling door onto Igloo

Outstanding issues

Rail Beam Assembly

Top Hexagon Assembly

Air & Power flow direction Glycol & Data direction

1214AD001

1214AD001

A

2.1.7 PFIS Cooler Boxes <-> PFIS Structure – 6e

2.1.7.1 Physicale) Dimensions of packaging space/s required by PFIS: TBDf) Cooling Capacity required for each: TBDg) Interface between Cooler Box and electronics Frame: TBD

2.1.8 Layout of Igloo behind Primary Mirror

PFIS ICD: 03/03/11

2.1.9 Cable List

Purpose Cable Source Cable Destination Required Current (A)Current requirements (per core) (A)No cores No cores for power calcsCross section (per core) for 0.5 deg temp risAreaLength (m) Description Cable OD

PFIS Computer

Electrical Room

UPS Computer Room 2 10 10

PXI ACElectrical Room UPS PFIS 2 60 10

Motor Ac

Electrical Room

UPS PFIS 2 60 10

Leach Controller

Electrical Room

UPS (Special) PFIS (Vis) 1 60 10Fiber Optic - Leach Controller

SAAO PC Computer Room PFIS (Vis) 2 60 Fiber 5

Fiber Optic - PXI

Chassis

PFIS PC

Computer room PFIS 1 60 Fiber 5RS232 - Etalon

Controller

PFIS PC

Computer room Top Hex (Vis) 4 40 Fiber 5

Queensgate: xyz Top Hex PFIS (Vis) 3 20 Coax 20

Queensgate: HV Top Hex PFIS (Vis) 3 20 10

Queensgate: AC

Electrical Room

UPS Top Hex (Vis) 2 40 10Star Tracker Head Payload Payload 15 5 10

Star Tracker AC

Electrical Room

UPS Payload 2 60 10Star Tracker Video Payload Computer Room 1 60 Fiber 5Star Tracker

Ethernet Payload Computer Room 2 60 Fiber 5Star Tracker

Serial Payload Computer Room 2 60 Fiber 5PFIS Contact Microphone PFIS Operator's Area 1 60 Coax (RG174) 5

Cryotiger coolant

supply Igloo - PM PFIS (Vis) 1 15 Braided steel 15Cryotiger Coolant

return PFIS (Vis) Igloo - PM 1 15 Braided steel 15Compressed dry

air - instr gr see payload sheet

Glycol see payload sheet

NOTE: Main Supply power is 220V ac - general mains and UPS

SALT-3190AS0002 SAAO Interface Control Document 1

Southern Africa Large Telescope

Prime Focus Imaging Spectrograph

SAAO Detector Subsystem

SALT-3190AS0002: SAAO Interface Control Document

SAAO PFIS Detector Subsystem Team: Darragh O’Donoghue

Luis Balona Etienne Bauermeister

Dave Carter Geoff Evans Willie Koorts

James O’Connor Faranah Osman

Stan van der Merwe

Issue 1.13

3 March 2003


Issue History

Number And File Name Person Issue Date Change History

saao.icd.doc WPK 1.8 26 Sep 2001 PFIS PDR issue SALT-3190AS0002 SAAO ICD Issue 1.9.doc

DOD 1.9 4 Nov 2002 First pre-PFIS CDR update

SALT-3190AS0002 SAAO ICD Issue 1.10.doc

1.10 6 Nov 2002 Major pre-PFIS CDR update


1.11 18 Feb 2003 Resolution of TBDs.


1.12 23 Feb 2003 Update with inclusion of cooler box I/F


1.13 03 Mar 2003 Final PFIS CDR update with inclusion of cryostat info

Table of Contents

1 Scope............................................................................................................................6

2 Optical..........................................................................................................................6

3 Mechanical...................................................................................................................6

3.1 Weight Budget .................................................................................................... 8

3.2 Envelope ........................................................................................................... 14

3.3 Mount Points..................................................................................................... 14

3.4 Centre of Gravity .............................................................................................. 15

3.5 Handling Fixtures.............................................................................................. 18

3.6 Shipping Container ........................................................................................... 18

4 Electrical ....................................................................................................................18

4.1 Electrical Power ................................................................................................ 18

4.2 Electrical Connectors ........................................................................................ 19

4.3 Signal Connectors ............................................................................................. 19

4.4 Shutter Control.................................................................................................. 19

5 Dry Air .......................................................................................................................20

6 Cryogenic and Refrigeration......................................................................................20

6.1 Cooler Box........................................................................................................ 21


7 Computers and Communications...............................................................................22

8 Software .....................................................................................................................22

9 Maintenance...............................................................................................................22

10 List of TBD And TBCs..........................................................................................23


PFIS

PXI Chassis

Motor Drivers

Etal

P

Control Room

Screens Keyboards

SAAO

DETECTOR

PACKAGE

Clean UPS

Fiber

+40, +24, +12, -12, +5

Twin Fiber 2xQuee

Cable

y

Electrical Power

Pneumatics

Coolant (Glycol or Cryotiger)

Control Signals

CCD Control and Data

Dry Instrument Air

Vacuum pumping

Figure 1 shows the PFIS/SALT block diagram

Top Hex

on Controllers

FIS Power

Igloo

Cryocooler

Cryotiger +Return

nsgate

2xRS232

Computer Room

PFIS PC:

PCON

ComputerRoom

SAAO PC:

PDET

Facilit

.


FACILITY

Shutter

Window purge Fr Transfer MaskCCD Cryostat

Cryotiger +Return

Thermal Ctrl Enclosure

Sub-System

Controller

PFIS PXI Chassis

Motor Drivers

Power Supply

Clean UPS

Ion Pump

Controller

Power Supply

Array

Controller

Igloo Cryocooler

Fiber Electrical Power

Pneumatics

Coolant (Glycol or Cryotiger)

Control Signals

CCD Control and Data

Dry Instrument Air

Vacuum pumping

Twin Fiber

Computer Room

PFIS PC: PCON

Computer Room

PFIS Detector PC: PDET

Figure 2 shows the SAAO part of Figure 1 in more detail.


1 Scope This document specifies the interfaces between the UW-Madison part of the Prime Focus Imaging Spectrograph (PFIS) and the SAAO-supplied Detector subsystem. The interfaces are optical, mechanical, electrical, cryogenic, software, and communications. There are no pneumatic interfaces between the Detector subsystem and PFIS. Figure 1 shows a block diagram with Figure 2 showing more detail in the SAAO detector subsystem.

Note that PFIS presents a single interface to the facility. Resources required by the PFIS subsystems (detector assembly and the etalons) are routed from the PFIS interface within the instrument. This is required for designing the PFIS wire harness.

2 Optical The optical interface between PFIS and the Detector subsystem is defined to be the cryostat window. During assembly and thereafter, this will be the field lens, the final optical element, of the PFIS camera. However, for testing of the cryostat, the field lens will not be available in South Africa. In any case current test plans involve mounting the cryostat on the SAAO 1-m telescope. Thus, a separate, optically flat, cryostat window will be needed and has been procured from Mount Stromlo and Siding Spring Observatories.

3 Mechanical Figure 3 shows various views of the mechanical design of the PFIS cryostat. The Cryostat Document (SALT-3197AE0001 Cryostat Issue 2.5.doc) specifies many aspects of the mechanical interface between the PFIS and the Detector subsystem more fully.


Figure 3 showing general views of the cryostat


Figure 3 (cont.) showing section views of the cryostat


Figure 3 (cont.) showing section views of the cryostat

3.1 Weight Budget The array controller and power supply are available in two versions – standard and large. Data for both is presented; one or the other option will be used. TBD2

Item Standard SDSU (kg)

Large SDSU (kg)

Array controller (populated with pcb’s) 6.5 10.5

Array controller power supply (including 3 m cable)

6.0 7.3

Cryostat 8.5 8.5

Ion pump controller 1.8 1.8

Subsystem controller & power supply 4.0 4.0

Cabling 1.0 1.0

TOTAL: 27.8 33.1


Figure 4 shows the Standard SDSU II array controller envelope and mounting point. Note that the large controller envelope sketch is to follow


Figure 5 shows the standard SDSU II power supply envelope and mounting point. Note that

the large power supply envelope sketch is to follow


Figure 6 shows the Sub-systems Controller and Power Supply box envelope and mounting point.


Figure 7 shows the Varian MicroVac Ion Pump Controller envelope and mounting point.


3.2 Envelope

Figure 3 shows the mechanical envelope for the detector housing. Allow an addition ~50 mm at ends carrying plugs.

Figure 4 shows the mechanical envelope for the standard array controller, measuring 360 x 175 x 140 mm. Allow an additional 100mm at each end for cabling – i.e. the 360mm dimension becomes 560mm. If the controller is to be fitted with a heat exchanger and insulated (see section 5), this envelope will have to be increased to 360 x 190 x 140 mm. An additional 20 mm on all three dimensions will be needed for the insulation.

If the larger array controller housing is required, the envelope increases to 360 x 175 x 280 mm with a corresponding increase for heat exchanger. Allow an additional 100mm at each end for cabling – i.e. the 360mm dimension becomes 560mm.

Figure 5 shows the mechanical envelope for the standard power supply, measuring 230 x 200 x 110mm. Allow an additional 100mm for cabling – i.e. the 230mm dimension becomes 330mm. If the larger power supply is required, the envelope increases to 312 x 210 x 134 mm.

Figure 6 shows the mechanical envelope of the subsystems controller, measuring 250 x 230 x 120 mm. Allow an additional 100mm for cabling – i.e. the 250mm dimension becomes 350mm.

Figure 7 shows the mechanical envelope of the ion pump controller, measuring 107 x 130 x 164 mm. Allow an additional 130mm for cabling – i.e. the 164mm dimension becomes 294mm.

3.3 Mount Points Figure 3 shows the detector housing mount plane being co-incidental with the optical focal plane as a 3-point kinematic system (ball-and-groove), centered on the optical axis, 35 mm behind the front surface of the cryostat window.

Figure 4 shows the standard size array controller mount point consisting of eight holes, tapped M6. Two of the holes at the fans are unusable (see Figure 4). Note that the end connecting to the detector housing has a connector length limit of 2000 mm wire length.

Figure 5 shows the standard power supply mount point consisting of 4 x M6 clearance holes.

Figure 6 shows the subsystems controller mount point consisting of 4 x M5 clearance holes.

Figure 7 shows the ion pump controller mount point.


3.4 Centre of Gravity The CG of the array controller shall lie within a volume of 15 x 15 x 15 mm centred on the locations as depicted in Figure 8. This must be updated if the heat exchanger type of controller is used.

The CG of the power supply shall lie within a volume of 10 x 10 x 10 mm centred on the locations as depicted in Figure 9.

The CG of the detector housing shall lie within a volume of 10 x 10 x 10 mm, measured 50 ± 5 mm with respect to its mount point as depicted in Figure 10.

Figure 8 shows the centre of gravity of the standard SDSU II array controller. (Update if the heat exchanger version is to be used).


Figure 9 shows the centre of gravity of the standard SDSU II power supply.


Figure 10 shows the centre of gravity of the detector housing.


Table 1: Systems power requirements for PFIS Detector Package

SYSTEM LOCATION VOLTAGE POWER

Array controller Power Supply Payload *UPS 220v 0.15 kW

Ion Pump Controller Payload UPS 220v 0.04 kW

Sub-Systems Controller Power Supply Payload UPS 220v 0.1 kW TBC1

*UPS = “Detector” UPS power.

3.5 Handling Fixtures The Detector Subsystem components shall accommodate cranes and hoists with suitably placed 1/2-13 threaded holes. Their location will depend on the detailed mechanical design, but should allow the components to be lifted in an attitude suitable for integration with the PFIS structure.

3.6 Shipping Container The Detector Subsystem components shall be delivered to UW in a container suitable for reuse in shipping the components to South Africa. The shipping container(s) shall provide for the safe transport of the components, and any tools and fixtures required to assemble, install, remove, and disassemble the Detector subsystem; it will be suitable for any combination of road, rail, air, or sea transportation.

4 Electrical This section specifies the electrical interface between the PFIS and the Detector subsystem.

4.1 Electrical Power Electrical power is provided by the facility and is described in the PFIS-PFIP ICD. Power requirements are listed in Table 1.

The mains power to the array controller is to be “clean” UPS power while the Cryotiger compressor is to be supplied from “dirty” UPS power. The clean UPS mains power will be fed to the SDSU power supply which will in turn provide power to the array controller and detector. The SDSU/CCD system must NOT be remotely controllable in order to avoid inadvertent switching off. Manual switch on/off only.


4.2 Electrical Connectors

The Detector subsystem shall use the same style electrical connectors as PFIS. The type is IEC type.

4.3 Signal Connectors The array controller is connected to its host computer via a dual optical fibre bundle (labeled Twin Fibre in Figure 1). This bundle shall be routed through the tracker wrap-up and will pass through the PFIS master interface panel without any interruption, i.e. the fibre optic is a point-to-point connection between the array controller on the one end and the host computer on the other end.

The fiber connector type is as supplied by ARC (Astronomical Research Cameras).

The array controller will also be connected to the detector cryostat by a cable no more than 2000 mm in length.

4.4 Shutter Control

The SDSU array controller uses one control signal for shutter open/close commands. A logic value of 0 will instruct the shutter to open, and a value of 1 to close.

Two TTL level shutter status signals will indicate that the shutter is in its fully open (logic 0) and fully closed position (logic 0).

The PFIS wire harness shall include wires for these signals. All electrical signals between the array controller and PFIS shall be optically isolated. The SDSU controller will have a 9-pin male D-type connector on the connector panel for shutter control. Opto-isolation will be done inside the PFIS PXI control box. Pinout function will be as follows:

Pin 1: Shutter control +V (300 ohms to +5 volts at SDSU end).

Pin 2: Shutter control signal = logical "0" to open shutter (open collector NPN transistor at SDSU end [there is a photodiode between pins 1 and 2 on PFIS end]).

Pin 3: Shutter open = logical "0" (open collector output of an opto-isolator on PFIS; SDSU has a 4.7K pullup to +5 volts).

Pin 4: Shutter closed = logical "0" (open collector output of an opto-isolator on PFIS; SDSU has a 4.7K pullup to +5 volts).

Pin 5: Shutter status signal return (SDSU signal ground; isolated from PFIS system ground).

Pins 6-8: N/C


Pin 9: PFIS chassis ground (for cable shield; if shield connected on PFIS, open at SDSU end to avoid chassis currents flowing on shield between systems).

5 Dry Air In order to prevent the detector cryostat window from misting over, a dry air purge is applied. The dry instrument air, as supplied by the facility will be clean enough for this purpose. The optics purge overpressure exit may act as the window dry air purge.

6 Cryogenic and Refrigeration The Detector subsystem requires both cryogenic cooling for the detector housing, and refrigeration for heat disposal from the SDSU detector array controller and its power supply, the ion pump controller, and the subsystems controller. Thus, the facility shall deliver glycol coolant to the PFIS master interface panel. The connector is specified in the PFIS/SALT ICD. The glycol shall be routed within the PFIS to the locations of the SDSU power supply, the SDSU array controller, the ion pump controller and the subsystems controller. The cooled components shall use the same type of connector. The type of connector is TBD7.

The cryocoolant will be routed from the Cryotiger compressor, through the Cryotiger hose to the detector housing. The Cryotiger hose shall be routed from the Igloo, up through the tracker wrap-up, and then to the PFIS master interface panel. Note that although this hose is relatively flexible to bend, it does not allow any movement in twist. This hose shall be a combination of flexible stainless steel hose (as supplied by the cryotiger manufacturer) and solid copper tubing to enable disconnection for maintenance purposes. Flexible hose shall arrive at the PFIS master interface panel. In contrast to earlier versions of this document, there shall be no break in the hose at the master interface panel; instead the hose shall be routed through the panel straight to the detector. The detector housing connector type is TBD6.

There are two possibilities of implementing the cooling of power supplies and controller units (TBD8) – either using a standard “SALT cooler box” (probably the best option for everything but the array controller. This solution is depicted in Fig. 4) or modify one or more external surface(s) to be a glycol heat exchanger and insulate the complete component (probably the best option for the array controller - most probably the side marked “HOT SIDE” in Figure 4). Although the array controller is shown in Fig. 2 as in the cooler box, if the heat exchanger option is used it will not be in the cooler box.


6.1 Cooler Box

Note that none of the options detailed below have a defined space for the heat exchanger as the heat exchanger details are currently unknown. There is unused volume in all the permutations which *may* be big enough for a heat exchanger.

Space has been allowed space for mounting the units inside the boxes such that air circulation holes/fans are not restricted.

The dimensions are internal requirements - the box wall thickness along with insulation is currently unknown. From conversations with Leon Nel, Payload and Tracker Sub-Project Manager, the payload cooler boxes will likely be 25 mm thick: 15 mm for structural material and 10 mm for insulation. It is therefore suggested that 50 mm is added on to the dimensions given below to assess the volume required.

The PFIS cold box possibilities work out to two options:

6.1.1 Option 1.

Two separate cold boxes, one for the SDSU controller crate, the second for the Sub-systems controller(SSC), Ion Pump controller and SDSU power supply. Dimensions used are assuming the large power and controller crate:

Box 1: SDSU controller

Internal dimensions, L x W x H: 670 x 320 x 240 mm.

Cable access through both end faces - i.e. the 320 x 240 mm faces.

One end face takes all the cabling to the detector cryostat, so must be oriented on the structure such that the resulting cable length to the cryostat is less than two meters.

Box 2: SDSU PSU, Ion Pump, SSC


Cable access through side face - i.e. a 400 x 250 mm face. This face

must be removable/opening for installation/removal of the units.

6.1.2 Option 2.

One single cold box that must be within 2m cable length of the cryostat.



Cable access through both end faces (the 320 x 420 mm faces) is most convenient, but we can organise things internally to utilize only one face if necessary. One end face must be within 2m cable length of the cryostat. Both end faces should be removable for installation/removal of the units.

7 Computers and Communications This section specifies the computer and communications interface between the PFIS and the Detector subsystem.

The array controller will be controlled with LabView on a Linux or “Real Time” (RT) Linux PC with a PCI backplane (labelled SAAO PC: PDET in Figure 1). The LabView front end will communicate with an RT Linux Module or a normal Linux C application which will control the array controller.

Communications between the PFIS and/or its control PC (PCON) and the Detector Subsystem PC (PDET) will be on Ethernet, under the control of LabView's network communications protocol.

The Detector Subsystem will provide (via standard LabView protocols) all relevant information about itself. The details are in the Software Document (SALT-3199AS0001 Software Issue 1.1.doc).

8 Software This interface is specified in the Software Document (SALT-3199AS0001 Software Issue 1.1.doc).

9 Maintenance The PFIS CCD cryostat will require occasional vacuum pump-downs at a frequency of around 6 months. This will be done with the cryostat in-situ, using a portable vacuum pump, connecting to the cryostat by means of a flexible vacuum hose. The portable vacuum pump will be secured in position as near as possible to the PFIS cryostat for the duration of the pump-down using suitable hooks, clamps, brackets, etc. the type and position(s) of which is to be agreed upon with SALT (TBD15). It should be noted that the shorter the vacuum hose between the vacuum pump and the cryostat, the better for achieving a good vacuum in a short time. The connector type will be a standard KF25 flanged vacuum connector.


Regeneration (vacuum baking) of the cryostat getter material will not be required at vacuum pumpdown since activated charcoal is to be used as the getter material. Charcoal outgases its cryopumped gas load when warmed up to room temperature. The cryostat will thus not be required to be opened up for vacuum maintenance.

10 List of TBD And TBCs

TBD1 - Total weight budget for detector subsystem

TBD2 - Standard or Large SDSU controller/power supply

TBD6 - Detector housing connector type

TBD7 - Cooled unit connector type

TBD8 - Alternative cooling schemes for array controller and its power supply

TBD15- Hook and clamps for securing the vacuum pump during vacuum maintenance

TBC1 - Subsystem controller power requirement.

- 1 -

Southern Africa Large Telescope

Prime Focus Imaging Spectrograph

Rutgers Etalon Subsystem

Interface Control Document

Revision 1.4

16 January 2002

- 2 -

1 Scope ...................................................................................................................... 3

2 Optical .................................................................................................................... 3

2.1 Collimation...................................................................................................... 3

3 Mechanical.............................................................................................................. 3

3.1 Weight Budget................................................................................................. 3

3.2 Envelope ......................................................................................................... 3

3.3 Center of Gravity............................................................................................. 3

3.4 Mount Point..................................................................................................... 4

3.5 Handling Fixtures ............................................................................................ 4

3.6 Shipping Container .......................................................................................... 4

4 Electrical ................................................................................................................. 4

4.1 Electrical Power .............................................................................................. 4

4.2 Electrical Connectors....................................................................................... 4

4.3 Signal Connectors............................................................................................ 4

5 Cryogenic................................................................................................................ 4

6 Pneumatic ............................................................................................................... 5

6.1 Pneumatic Connectors ..................................................................................... 5

7 Computers and Communications ............................................................................. 5

8 Software.................................................................................................................. 5

8.1 Commands ...................................................................................................... 5

8.2 Telemetry ........................................................................................................ 6

- 3 -

1 Scope

This document specifies the interfaces between the UW-Madison part of the Prime FocusImaging Spectrograph (PFIS) and the Rutgers-supplied Etalon subsystem. The interfacesare optical, mechanical, electrical, cryogenic, pneumatic, software, and communications.

Figure 1 shows the PFIS/SALT block diagram.

Note that PFIS presents a single interface to the facility. Resources required by the PFISsubsystems (detector assembly and the etalons) are routed from the PFIS interface withinthe instrument. This is required for designing the PFIS wire harness.

2 Optical

This section specifies the optical interface between the PFIS and the Etalon subsystem.

Figure TBD shows the optical design of the PFIS.

The optical interface between PFIS and the Etalon subsystem is define to be TBD.

2.1 Collimation

The degree of collimation at the optical interface is TBD.

3 Mechanical

This section specifies the mechanical interface between the PFIS and the Etalonsubsystem.

Figure TBD shows the mechanical design of the PFIS.

3.1 Weight BudgetThe Etalon subsystem has a weight budget of TBD kg per Etalon assembly.

3.2 EnvelopeFigure TBD shows the mechanical envelope for the Etalon subsystem.

3.3 Center of Gravity

Each Etalon assembly can be in two states, in or out.

When in, the CG of each Etalon assembly must lie within a volume of TBDxTBDxTBDmm, measured TBD with respect to its mount point.

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When out, the CG of each Etalon assembly must lie within a volume of TBDxTBDxTBDmm, measured TBD with respect to its mount point.

3.4 Mount Point

Figure TBD shows PFIS mount point for an Etalon assembly.

3.5 Handling Fixtures

The Etalon assemblies shall accommodate cranes and hoists with suitably placed 1/2-13threaded holes. Their location will depend on the detailed mechanical design, but shouldallow the Etalon assemblies to be lifted in an attitude suitable for integration with thePFIS structure.

3.6 Shipping Container

The Etalon subsystem shall be delivered to UW in a container suitable for reuse inshipping the Etalon subsystem to South Africa. The shipping container(s) shall providefor the safe transport of the Etalon assemblies and all components and optical elements,and any tools and fixtures required to assemble, install, remove, and disassemble theEtalon subsystem.

The shipping container will be suitable for any combination of road, rail, air, or seatransportation.

4 Electrical

This section specifies the electrical interface between the PFIS and the Etalon subsystem.

4.1 Electrical Power

Electrical power is provided by the facility and is described in the PFIS-PFIP ICD.

4.2 Electrical Connectors

The Etalon subsystem shall use the same style electrical connectors as PFIS. The type isTBD.

4.3 Signal Connectors

Each Etalon assembly has two signal connectors, one for the Queensgate controller cableand one for controlling the insertion mechanism.

The mechanism control connector type is TBD. Table TBD shows the pinout.

5 Cryogenic

There are no cryogenic requirements for the Etalon subsystem.

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6 Pneumatic

This section specifies the pneumatic interface between the PFIS and the Etalonsubsystem.

The Etalon subsystem will use pneumatic control for the etalon mechanisms. The air isprovided by the facility, and is described in the PFIS-to-PFIP ICD.

6.1 Pneumatic ConnectorsThe Etalon subsystem shall use the same style pneumatic connectors as PFIS. The type isTBD.

7 Computers and CommunicationsThis section specifies the computer and communications interface between the PFIS andthe Etalon subsystem.

The Etalon subsystem will be controlled with LabView on a Linux PC with a PCIbackplane.

The Etalon assemblies will be controlled with a Queensgate etalon controller over aproprietary Queensgate cable.

The Queensgate etalon controller will be controlled from the PC on a RS232 line.

The Etalon Assembly mechanisms will be actuated with motors or pneumatics (TBD). Ineither case, the control will be through a PCI card interface compatible with the controlinterfaces used for the other PFIS mechanisms. The PFIS and Etalon subsystem PIs willagree on a controls plan that is acceptable to both teams.

8 Software

This section specifies the software interface between the PFIS and the Etalon subsystem.

The Etalon subsystem will be controlled with LabView on a Linux PC, and the Etalonsubsystem PI will provide a LabView Virtual Instrument (VI) for the Etalon subsystem.

We anticipate that no C code will be needed to control the Etalon subsystem.

8.1 Commands

The Etalon subsystem will execute the following commands.

• Etalon 1/2 in/out

• Etalon x/y/z set (set tip/tilt/gap to new values)

• Etalon x/y/z adjust (adjust previously sent values)

The Etalon LabView VI will provide all suitable software interlocks to prohibit anycommanded operation from performing an illegal operation. In no instance will it bepossible to damage any component with any combination of commands.

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8.2 Telemetry

The Etalon LabView VI shall provide, via standard LabView methods, the followinginformation.

• Etalon 1/2 position/status

• Subsystem status (includes error status for illegal commands, etc)

Documents

PFIS INTERFACE CONTROL DOCUMENT cdr/c… · PFIS ICD Note: 1) The system specification requires that no subsystem in the optical path should: • have a surface temperature of more