Mechanism Information

The following pages list the mechanisms, each mechanism is listed in numerical order on at least a single page, a description of the mechanism, relevant operational limits and commands are listed. Space is left for other findings to be included against each mechanism, it is therefore important to use the copy of this document kept in the WHT control room, if you do make any findings that you consider may be of value, please included them in the space provided for future reference, include extra pages if necessary.

Summary of mechanisms
 
ADI  ADC Inner Element
ADO ADC Outer Element
AFS PFIP Autoguider Focus Slide
AFW PFIP Autoguider Focus Wheel
APX PFIP Autoguider Probe X axis
APY PFIP Autoguider Probe Y axis
DOR PFIP Access Door
HUM PFIP Relative Humidity and Temperature
MFW PFIP Main Filter Wheel
PFM Prime Focus Mode
SHS PFIP Shutter Status

ADI

Instrument .................................Atmospheric Dispersion Corrector

Mechanism name ......................ADC inner element

Mechanism type .......................Stepper motor driven rotary mechanism with limit sensors restricting rotation to 180 degrees.

Operational range ......................+90.0 to -90.0 in 0.1 degree increments

Resolution ..................................0.3 degrees

Encoder type .............................12 bit digital, absolute rotary encoder.

Network commands ..................Move ADI1O1(+900 to -900)

...................................................Datum ADI102

...................................................Stop ADI100

...................................................Status requests ADI200 and ADI201

Network responses ..................ADI800, ADI801, ADI802, ADI803, ADI804

Response parameters ...............( EEcmd, EEmech, Pos, Dtm, 0 )

..................................................EEcmd - Command errors in hex

..................................................EEmech - Mechanism errors in hex

..................................................Pos - Current position in decimal

.................................................Dtm - Datum offset in decimal

change in position for 802 +/- 0.6 degrees

Mechanism errors ...................01, 02, 03, 05,06, 07, 08, OA, OD, 11, 19, 20,21, 25

Interlocks ................................None

Datum sensor - used by datum command.

Limit sensors - Restrict rotation to +/- 90 degrees

Limpit used - ADC Limpit

Limpit channel - Y (1)

Limpit drive - 1 (Y)

Limpit Multiplexer - None

Limpit Home/Datum - Used, encoder confidence check.

Limpit drive brake - None

Limpit Barcode reader - Not used

Limpit commands used - SMDC, IN, RMOVE, PARAM, WHERE, DMOVING, DSTOP

ADO

Instrument ..................................Atmospheric Dispersion Corrector

Mechanism name .......................ADC outer element

Mechanism type ........................Stepper motor driven rotary mechanism with limit sensors restricting rotation to 180 degrees.

Operational range ......................+90.0 to -90.0 in 0.1 degree increments

Resolution ..................................0.3 degrees

Encoder type .............................12 bit digital, absolute rotary encoder.

Network commands ..................Move ADO101(+900 to-900) Datum ADO102

...................................................Stop ADO101

...................................................Status requests ADO200 and ADO201

Network responses ..................ADO800, ADO801, ADO802, ADO803, ADO804

Response parameters ..............( EEcmd, EEmech, Pos, Dtrn)

.................................................EEcmd - Command errors in hex

.................................................EEmech - Mechanism errors in hex

.................................................Pos - Current position in decimal

.................................................Dtm - Datum offset in decimal

change in position for 802 +/- 0.6 degrees

Mechanism errors ....................01, 02, 03, 05, 06, 07, 08, 0A, 0D, 11, 19, 20,21, 25

Interlocks .................................None

Datum sensor - used by datum command.

Limit sensors - Restrict rotation to +/- 90 degrees

Limpit used - ADC Limpit

Limpit channel - X (0)

Limpit drive - 1 (Y)

Limpit Multiplexer - None

Limpit Home/Datum - Used, encoder confidence check.

Limpit drive brake - None

Limpit Barcode reader - Not used

Limpit commands used - SMDC, IN, RMOVE, PARAM, WHERE, DMOVING, DSTOP

AFS

Instrument .............................Prime Focus Instrument Platform

Mechanism name ..................Autoguider Focus Slide

Mechanism type ...................Stepper motor driven linear mechanism with limit sensors restricting movement to operational range.

Operational range .................14100um in 10 um increments

Resolution ............................10um

Encoder type ........................linear analogue encoder.

Network commands .............Move AFS101(0 to 14100)

.............................................Datum AFS102

.............................................Stop ANS100

Status requests ....................AFS200 and AFS201

Network responses .............AFS800, AFS801, AFS802, AFS803, ADO804

Response parameters .........( EEcmd, EEmech, Pos, Dtm, 0 )

.............................................EEcmd - Command errors in hex

.............................................EEmech - Mechanism errors in hex

.............................................Pos - Current position in decimal

.............................................Dtm - Datum offset in decimal

change in position for 802 +/- 30um

Mechanism errors ...............01, 02, 03,04, 05, 06, 07, 08, 0A, 0B, 0D, 0F, 11, 17, 18,19, 1A, 1B, 1C,1D,1E,1F, 20, 21,25

Interlocks ............................None

Datum sensor - used by datum command.

Limit sensors - Restrict movement to operational range

Limpit used - PFIP Limpit

Limpit channel - Either X (0) or Y (1)

Limpit drive - 2

Limpit Multiplexer - 1

Limpit Home/Datum - Used, encoder confidence check.

Limpit drive brake - None

Limpit Barcode reader - Not used

Limpit commands used - SMCM, IN, RMOVE, PARAM, WHERE, DMOVING, DSTOP

AFW

Instrument.......................... Prime Focus Instrument Platform

Mechanism name ...............Autoguider Focus Wheel

Mechanism type ................Stepper motor driven rotary mechanism.

Operational range ..............6 filter positions

Resolution .........................1 filter positions

Encoder type .....................none.

Network commands ...........Move AFW101(1 to 6)

...........................................Datum AFW102

...........................................Stop AFW100

Status requests ..................AFW200 and AFW201

Network responses ...........AFW800, AFW801, AFW802, AFW803, AFW804

Response parameters .......( EEcmd, EEmech, Pos, Dtm, 0)

............................................EEcmd - Command errors in hex

............................................EEmech - Mechanism errors in hex

............................................Pos - Current position in decimal

............................................Dtm - Datum offset in decimal

change in position for 802 Change not detected

Mechanism errors ..............01, 02, 03,04, 05, 06, 07, 08,0A,0B,0D,0F, 11, 17, 18, 19,1A,1B,1C,1D, 1E,1F, 20, 21, 25

Interlocks ...........................None

Datum sensor - used by datum command and move commands.

Limit sensors - None

Limpit used - PFIP Limpit

Limpit channel - Either X (0) or Y (1)

Limpit drive - 2

Limpit Multiplexer - 2

Limpit Home/Datum - Used, defines position 1.

Limpit drive brake - None

Limpit Barcode reader - Not used

Limpit commands used - SMCM, IN, RMOVE, PARAM, WHERE, DMOVING, DSTOP

APX

Instrument ..............................Prime Focus Instrument Platform

Mechanism name ...................Autoguider Probe X axis

Mechanism type ....................Stepper motor driven linear mechanism with limit sensors restricting movement to operational range.

Operational range ..................110,000um in 10 um increments

Resolution .............................10 um linear analogue encoder.

Network commands ..............Move APX101(0 to 110000)

Datum ...................................APX102

Stop ......................................APX100

Status requests .....................APX200 and APX201

Network responses ..............APX800, APX801, APX802, APX803, APX804

Response parameters ...........( EEcmd, EEmech, Pos, Dtm, 0 )

..............................................EEcmd - Command errors in hex

..............................................EEmech - Mechanism errors in hex

..............................................Pos - Current position in decimal

..............................................Dtm - Datum offset in decimal

change in position for 802 +/- 60um

Mechanism errors ................01, 02, 03,04, 05, 06, 07, 08, 0A, 0B, 0D, 0F, 11, 17, 18,19,1A,1B,1C,1D,1E,1F, 20, 21, 25

Interlocks ............................None

Datum sensor - used by datum command.

Limit sensors - Restrict movement to operational range

Limpit used - PFIP Limpit

Limpit channel - Either X (0) or Y (1)

Limpit drive - 1

Limpit Multiplexer - 4

Limpit Home/Datum - Used, encoder confidence check.

Limpit drive brake - Used

Limpit Barcode reader - Not used

Limpit commands used - SMCM, IN, RMOVE, PARAM, WHERE, DMOVING, DSTOP

APY

Instrument............................ Prime Focus Instrument Platform

Mechanism name .................Autoguider Probe Y axis

Mechanism type ..................Stepper motor driven linear mechanism with limit sensors restricting movement to operational range.

Operational range .................20,000um in 10 um increments

Resolution ............................10 um

Encoder type ........................linear analogue encoder.

Network commands .............Move APY101(0 to 20000)

.............................................Datum APY102

.............................................Stop APY100

Status requests ....................APY200 and APY201

Network responses .............APY800, APY801, APY802, APY803, APY804

Response parameters ..........( EEcmd, EEmech, Pos, Dtm, 0 )

...............................................EEcmd - Command errors in hex

...............................................EEmech - Mechanism errors in hex

...............................................Pos - Current position in decimal

...............................................Dtm - Datum offset in decimal

change in position for 802 +/- 60um

Mechanism errors .................01, 02, 03,04, 05, 06, 07, 08,0A,0B,0D,0F,11, 17, 18,19, 1A,1B,1C,1D, 1E,1F, 20, 21,25

Interlocks ..............................None

Datum sensor - used by datum command.

Limit sensors - Restrict movement to operational range

Limpit used - PFIP Limpit

Limpit channel - Either X (0) or Y (1)

Limpit drive - 1

Limpit Multiplexer - 2

Limpit Home/Datum - Used, encoder confidence check.

Limpit drive brake - Used

Limpit Barcode reader - Not used

Limpit commands used - SMCM, IN, RMOVE, PARAM, WHERE, DMOVING, DSTOP

DOR

Instrument............................Prime Focus Instrument Platform

Mechanism name ................Access door

Mechanism type ..................microswitch.

Operational range ...............Open (0) or Closed (1)

Network commands ...........Status requests DOR200 and DOR201 DOR800, DOR801, DOR802, DOR803, DOR804

Network responses ............( EEcmd, EEmech, Pos, Dtm, 0)

Response parameters ...........EEcmd - Command errors in hex

.............................................EEmech - Mechanism errors in hex

.............................................Pos - Current position in decimal

.............................................Dtm - Datum offset in decimal

.............................................Change in state

change in position for 802 None

Mechanism errors ................interlocks MFW when open

Interlocks .............................PFIP Limpit

Limpit used

HUM

Instrument ................................Prime Focus Instrument Platform

Mechanism name ......................Relative Humidity and Temperature.

Mechanism type .......................Humidity and Temperature sensor module.

Operational range .....................Humidity 10 to 90 % +/- 5%

Temperature .............................0 to 50 C +/- 1C.

Network commands .................Status requests HUM200 and HUM201

Network responses ..................HUM800, HUM804

Response parameters ...............( EEcmd, EEmech, Pos, Dtm, 0)

.....................................................EEcmd - Command errors in hex

.....................................................EEmech - Mechanism errors in hex

.....................................................Pos - Current position in decimal

.....................................................Dtm - Datum offset in decimal

Mechanism errors .......................24

Interlocks ...................................none.

Limpit used ................................PFIP Limpit.

MFW

Instrument ..................................Prime Focus Instrument Platform

Mechanism name .......................Main Filter Wheel

Mechanism type ........................Stepper motor driven rotary mechanism with stepper motor driven locating detent.

Operational range ......................7 filter positions, 2 detent positions,1 read Barcode only.

..................................................-7 to-1 Move to filter position leaving detent out, no barcode read.

·..................................................0 Read Barcode only.

...................................................1 to 7 Move to filter position, locate wheel using detent, read barcode.

Resolution ..................................1 filter position

Encoder type .............................Filter barcode.

Network commands ..................Move MFW101(-7to+7)

...................................................Datum MFW102

...................................................Stop MFW100

...................................................Status requests MFW200 and MFW201

Network responses ..................MFW800, MFW801, MFW802, MFW803, MFW804

Response parameters ...............( EEcmd, EEmech, Pos, Dtm, 0)

...................................................EEcmd - Command errors in hex

...................................................EEmech - Mechanism errors in hex

...................................................Pos - Current position in decimal

...................................................Dtm - Datum offset in decimal

change in position for 802 Change not detected

Mechanism errors ....................01, 02, 03,04, 08, 15, 16, 17, 18, 19,1A,1B,1C,1D,1E,1F, 21, 22, 23, 25, 26

Interlocks ..................................Interlocked by access door

Datum sensor -used by datum command and move commands.

Limit sensors - None

Limpit used - PFIP Limpit

Limpit channel - Either X (0) or Y (1)

Limpit drive - 1 ( detent drive 4 also used)

Limpit Multiplexer - 3

Limpit Home/Datum - Used, defines position 1.

Limpit drive brake - Used

Limpit Barcode reader - used

Limpit commands used - SMCM, BARCODE, IN, RMOVE, PARAM, WHERE, DMOVING, DSTOP

PFM

Mechanism name .............................Prime Focus Mode

Mechanism type ...............................none.

Operational range .............................PFIP and ADC (0) or ADC only (1) modes.

Network commands .........................Move PFM101(0 or 1)

.........................................................Status requests PFM200 and PFM201

Network responses ..........................PFM800, PFM801, PFM802, PFM803, PFM804

Response parameters ........................( EEcmd, EEmech, Pos, Dtm, 0 )

.............................................................EEcmd - Command errors in hex

.............................................................EEmech - Mechanism errors in hex

.............................................................Pos - Current position in decimal

Mechanism errors ...............................04

Interlocks ..........................................When ADC only mode selected, power is removed from PFIP LIMPIT and PFIP specific network commands will not be available.

Limpit used .......................................none

SHS

Instrument ........................................Prime Focus Instrument Platform

Mechanism name .............................Shutter Status

Mechanism type ...............................microswitches on shutter mechanism.

Operational range .............................Jammed (0), Open (1), Closed (2), Disconnected (3)

Network commands .........................Status requests SHS200 and SHS201

Network responses ..........................SHS800, SHS804

Response parameters .......................( EEcmd, EEmech, Pos, Dtm, 0)

............................................................EEcmd - Command errors in hex

............................................................EEmech - Mechanism errors in hex

............................................................Pos - Current position in decimal

Mechanism errors ..............................04, 09.

Interlocks ...........................................None

Limpit used .......................................PFIP Limpit