Solenoid Controls Redesign
From GlueXWiki
To-do for solenoid controls redesign
- Recommendations from Director's Review: Electrical System and Quench Protection and Lehman Review
- determine if cold diodes can increase quench detection
- add fast DAQ system prior to testing first coil
- add tests for internal shorts, shorts to ground and ground faults in coil and power supply to start-up sequence
- add second dump circuit breaker
- add additional quench circuit diodes
- add second quench detector (connected to second dump breaker)
- add center tap to dump resistor and monitor ground current in the PLC
- add UPS on dump breakers to avoid fast discharges
- perform Failure Modes and Effects Analysis (FMEA)
- Infrastructure
- get fourth rack, install temporary wheels, bolt to other three racks, install computer and other equipment
- Cryo system
- need specs, new channels, new functionality, etc. from Jonathan
- Wiring
- document trip chains
- label circuit breakers
- use Sequence-Of-Events (SOE) module, need additional wiring and relays
- prototype use of SOE module and relays in controls test stand
- improve voltage range and eliminate cross-talk on voltage tap channels
- change connection scheme?
- change current limiting scheme?
- requirements: fast vs slow, high vs low voltage, high vs low precision
- Cody will look into this
- Danfysik power supply
- use 435NBX to talk to power supply
- choose ground fault detection mechanism
- lockbox for door key
- lock/tag/try procedures for dump resistor
- procedures to check for dump resistor integrity and diode polarity prior to startup
- Quench detector
- can we get a good balance...need sub-coil inductances from Floyd (Fall 2011)
- do we need a second QD? second technology? do we need to design our own?
- can we get an FPGA module with A/D inputs off the shelf to do this?
- Instrumentation
- implement system to isolate fault detectors and determine time sequence of trips
- implement RS232 connections to all devices (e.g. vacuum gauges)
- Use RTI 435NBX instead of Point I/O serial modules
- Replace shunt with flux-monitoring sensor
- VME-based fast DAQ
- NI vs VME?
- connection to PLC?
- connection to EPICS?
- A-B HMI improvements
- fault sequence screens
- Viewpoint
- get screens on the web
- security?
- EWEB
- create tag lists
- security?
- A-B PLC programming
- consider existing program a prototype, rework for 15-20 year lifetime
- send Josh to A-B training?
- custom ("add-on") instructions to simplify everything
- use function block, structured text and ladder logic as appropriate
- EPICS
- new channels
- UPS power
- solenoid controls racks
- Danfysik control circuits and contactor?
- target? other cryo and vacuum systems?
- cooling systems (dewpoint)?
- downtime due to power loss is deciding factor
Notes
- max ramp rate in the hall is approximately 10V / 20H = 0.5 A/sec
Possible future improvements
- monitor selected circuit breakers so operators can quickly find them when they trip