Add Motor Rack Control Functions

Modification Request #1 (C1 2006)

1. Introduction

We are adding features (digital control functions) to the Motor Rack. These will allow remote control of refrigerator drives, a vacuum pump, and a vacuum valve.

2. Background

Motor Rack M&C specification document is attached. This document defines the control addresses and bits to be added.

There are five Refrigerator Power Supply chassis (1-5) in the Motor Rack. Each one has five drive output ports (S1-S5) which are controlled independently. Therefore five control bits are required for each chassis, 25 in total. Setting a control bit to 1 turns the associated refrigerator motor drive OFF. Because of a shortage of control bits in the Motor Rack MCB interface, the 25 bits are scattered over five control addresses. Changing one bit must not affect others sharing the same address.

These controls will normally be used only by engineers and operators, so the primary interface will be via a Cleo screen or Device Explorer (for monitoring) and a configuration file. Basically we want it so that an engineer, technician, or operator can easily turn a specific drive port OFF or ON. Yet, we should try to minimize the chance of accidental changes by making control accessible only by editing the configuration file. The Cleo screen will be used only for monitoring the values.

Vacuum Control

Two control bits have been added for Vacuum Pump control and for Vacuum Valve control. The same comments about control via configuration file and monitoring via Cleo apply.

State Memory

It is quite important that the system not turn off refrigerators that should be running. (It takes about 2 days to recover if a cryo system warms up. If heaven forbid all the refrigerators warm up it could take a couple of weeks to fully recover.) It is also potentially damaging to equipment if a refrigerator runs for a long period when it is supposed to be off, or if a vacuum valve opens that is supposed to be closed. So, the system must be as robust as possible. The hardware power-up state is designed to put the control bits in a safe mode until the M&C system resets values. Because of these considerations, we request the following:

The 27 new control bits' state should be kept in non-volatile memory (e.g. a disk file), updated by editing the file, then cycling the manager to standby or off, then on again. (I believe this is practical because changes will be infrequent - done by people only.) The software should load this file at startup so that the last state is maintained across reboots, version changes, etc. Change will be effected by editing the motorrack configuration file, then cycling the manager state off and on. (i.e. The configration is re-loaded whenever the manager enters the "On" state.)

The software, by periodically checking, should notice and correct if readbacks of the 27 control bits do not agree with the expected state. This will prevent the hardware from running in the power-up state for long periods should a power dip in the Receiver Room cause the SIB to reset itself. Note: This feature is disabled when the manager set to the 'Off' state.

3. Design

The Motor rack coordinator has five refrigerator managers and a feed defroster manager. This MR will add a vacuum control manager, and augment the existing refrigerator managers. The feedback paramter names and mapping to managers is shown in the table below:

Description	SIB Address	Bit	Manager	Feedback Parameter Name	Parameter Type
Pump On/Off Control	4A	5	VacuumControl	vac_pump_control	enum On,Off
Valve On/Off Control	4A	6	VacuumControl	vac_valve_control	enum Closed,Open
Refr Supply1, Drive S1	48	0	RefrigeratorPowerSupply1	refr_supply_drive_S1	enum On,Off
Refr Supply1, Drive S2	48	1	RefrigeratorPowerSupply1	refr_supply_drive_S2	enum On,Off
Refr Supply1, Drive S3	48	2	RefrigeratorPowerSupply1	refr_supply_drive_S3	enum On,Off
Refr Supply1, Drive S4	48	3	RefrigeratorPowerSupply1	refr_supply_drive_S4	enum On,Off
Refr Supply1, Drive S5	4C	0	RefrigeratorPowerSupply1	refr_supply_drive_S5	enum On,Off
Refr Supply2, Drive S1	4C	1	RefrigeratorPowerSupply2	refr_supply_drive_S1	enum On,Off
Refr Supply2, Drive S2	4C	2	RefrigeratorPowerSupply2	refr_supply_drive_S2	enum On,Off
Refr Supply2, Drive S3	4C	3	RefrigeratorPowerSupply2	refr_supply_drive_S3	enum On,Off
Refr Supply2, Drive S4	4D	0	RefrigeratorPowerSupply2	refr_supply_drive_S4	enum On,Off
Refr Supply2, Drive S5	4D	1	RefrigeratorPowerSupply2	refr_supply_drive_S5	enum On,Off
Refr Supply3, Drive S1	4D	2	RefrigeratorPowerSupply3	refr_supply_drive_S1	enum On,Off
Refr Supply3, Drive S2	4D	3	RefrigeratorPowerSupply3	refr_supply_drive_S2	enum On,Off
Refr Supply3, Drive S3	4D	4	RefrigeratorPowerSupply3	refr_supply_drive_S3	enum On,Off
Refr Supply3, Drive S4	4D	5	RefrigeratorPowerSupply3	refr_supply_drive_S4	enum On,Off
Refr Supply3, Drive S5	4D	6	RefrigeratorPowerSupply3	refr_supply_drive_S5	enum On,Off
Refr Supply4, Drive S1	4D	7	RefrigeratorPowerSupply4	refr_supply_drive_S1	enum On,Off
Refr Supply4, Drive S2	4E	0	RefrigeratorPowerSupply4	refr_supply_drive_S2	enum On,Off
Refr Supply4, Drive S3	4E	1	RefrigeratorPowerSupply4	refr_supply_drive_S3	enum On,Off
Refr Supply4, Drive S4	4E	2	RefrigeratorPowerSupply4	refr_supply_drive_S4	enum On,Off
Refr Supply4, Drive S5	4E	3	RefrigeratorPowerSupply4	refr_supply_drive_S5	enum On,Off
Refr Supply5, Drive S1	4E	4	RefrigeratorPowerSupply5	refr_supply_drive_S1	enum On,Off
Refr Supply5, Drive S2	4E	5	RefrigeratorPowerSupply5	refr_supply_drive_S2	enum On,Off
Refr Supply5, Drive S3	4E	6	RefrigeratorPowerSupply5	refr_supply_drive_S3	enum On,Off
Refr Supply5, Drive S4	4E	7	RefrigeratorPowerSupply5	refr_supply_drive_S4	enum On,Off
Refr Supply5, Drive S5	4A	7	RefrigeratorPowerSupply5	refr_supply_drive_S5	enum On,Off

4. Deployment Checklist

Check functionality.
Documentation Written:35207d001.pdf: M&C Specification Document
Train relevant Engineers, Technicians, and Operators on procedures for updating the configuration files.
No Fits changes, or config_tool modifications required.
Cleo screen required. Ron is aware of this and is working with electronics on the specifications.

5. Test Plan

Once the control parameters have been added, we will test by seeing that the expected control bits change using a voltmeter connected to the MCB interface or controlled equipment.
Restart the MotorRack manager process to verify the state is retained across runs of the manager.

Signatures

APPROVED: I acknowledge that my request is fully contained in this MR, and if the SDD delivers exactly what I specified, I will be happy.

ACCEPTED: I acknowledge that I have validated the completed code according to the acceptance tests, and I am happy with the results.

Written	- JoeBrandt, RogerNorrod - 08Dec2005
Checked	- MarkClark - 08 Mar 2006
Approved by Sponsor	- RogerNorrod - 21Mar06
Approved by CCC	- JohnFord - 10Apr06
Accepted/Delivered by Sponsor	- RogerNorrod - 07Apr06

Symbols:

Use %X% if MR is not complete (will display )
Use %Y% if MR iscomplete (will display )

CCC Discussion Area

-- NicoleRadziwill - 06 Dec 2005

Attachment:	Action:	Size:	Date:	Who:	Comment:
35207d001.pdf	action	15468	07 Dec 2005 - 19:41	RogerNorrod	M&C Specification Document

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