Controls Meeting 1-Dec-2011
- Minutes from previous meeting 17-Nov-2011
- Equipment orders - Mark, Hovanes
- Solenoid_Controls_Redesign - Mark, Josh, Scot, Cody, Yi, Elliott
- coil taps
- 17 taps plus vapor-cooled leads plus splices
- one connection to fast daq and one to PLC, isolated somehow, account for range and precision
- additional connections to quench detector, not isolated
- Danfysik quench detector
- changes to cryo control system
- shunt replacement
- UPS power to Danfysik
- ground fault detector using dump resistor
- redundant Danfysik contactor, quench detector, dump diodes?
- need 4 NI fast daq modules, 8 chan/module
- coil taps
- Experiment Control Supervisor - Vardan, Hovanes, Elliott
- use CSS?
- EPICS evaluation
- alarm system
- EPICS - Nerses, Hovanes, Elliott
- JLab discriminator
- directory structure
- Controls test stand - Hovanes, Josh
- SOE module
- 435NBX serial module
- EPICS drivers and gui's
- PLC programming, Viewpoint, licenses, etc. - Josh
- high-priority tasks
- add-on instructions -- ladder logic, function block, structured text
- Elog - Elliott
- Midas elog
- Operator elog
- Mantis task tracker
- PyIRMIS - Hovanes, Elliott
9:30 AM Thurs 1-Dec-2011 CC L207
Thurs 1-Dec-2011 9:30am CC L207
Present: Elliott W, Hovanes E, Mark S, Josh B.
Mark still has a number of items to order.
Solenoid Controls Redesign
Current plans are to connect all coil taps to both the fast and slow DAQ systems. One resistor on a coil tap will be used for this, another will be used to connect to the quench detector, if needed. It still is not clear what kind of isolation amplifier we should use to isolate the connection to the DAQ systems. The QD will connect directly to its resistor.
Elliott reported that on the bench the QD seems to operate as advertised. As delivered and used in the Test Lab it could only compensate for about a 10% inductance imbalance, which agrees with Mark's recollections. With simple modifications it can handle much larger imbalances, Elliott will work out what we need. Note that the current limiting resistors have to be accounted for, and they may have to be modified. We agreed on using three QD channels in the hall, one for coils (1,4), one for (2,3), and a redundant channel for (2+1,3+4). Finally we plan to use the PLC as a redundant QD system.
Mark needs to order the shunt replacement and will implement the ground fault detector using the dump resistor.
Yi is happy with the new NI boxes, will order four total to give 32 fast DAQ channels.
We discussed whether it would be useful to use additional carbon resistors to measure the LHe level in the new tank, given the unreliability of the usual LHe level probes. It is not clear new resistors could be easily installed. The concern is to make sure we know the LHe level, as LHe loss can cause major damage. Some argued we have enough related measurements so this isn't a problem.
We are investigating whether Accelerator will interface the CSS-based archive display system to their MyA back-end archive system on a suitable time scale for us. Hovanes and Elliott will pursue this with Arne et al. Hovanes thinks this would be the ideal solution for us.
Controls Test Stand
Josh will check the SOE and NBX modules.
Josh will attend A-B school on project organization and management in Jan. Hovanes suggested we dump the A-B programs into XML and store them in SVN. Josh and Hovanes will check this out.