Experimental Physics and
Industrial Control System

• Thermocouples connected to a Greenspring thermocouple industry pack on a VME IP carrier  - cost per channel ~ $102
• Thermocouples connected to a Hytec instrumentation amplifier /ADC industry pack   - cost per channel ~ $70
• A semiconductor temperature sensor (National semiconductor LM35 ~ -55oC to 180oC, +/- 2oC accuracy +/- 0.5 oC resolution) giving ~ 10mV/oC directly connected to our standard ADC - cost per channel ~ $95

We have cable lengths of ~50m, to existing VME crates without problems, but larger distances would also probably be fine if you want to reduce the number of crates - but you need to trade off cable costs vs crate costs.

The total costs including VME crates, CPUs,  and special (thermocouple) cabling , based on your requirements, using 4 distributed crates, and an average cable length of 20m,  would be ~$120K.
 

Regards
Steve Hunt

"Rarback, Harvey" wrote:

        Folks,

We need to monitor about 700 thermocouples for the SPEAR3 upgrade.  There will be about 40 TCs on 18 girders distributed around the 230m ring circumference.
The present plan is to monitor the temperatures at a few second intervals.  We have a couple of quotes from PLC vendors, but they are fairly expensive.

Does anyone have a suggestion for hardware and software to accomplish our task?  Of course the aim is to get the temperatures into an IOC.

                                   --Harvey
   ----
Harvey Rarback                        phone:      (650)926-3963
Stanford Linear Accelerator Center    fax:        (650)926-4100
2575 Sand Hill Road                   home phone: (650)560-9111
Menlo Park, CA 94025
[email protected]

Replies:

Re: How to monitor 700 thermocouples? Ralph . Lange

MEDM display memory usage Robert Willson

References:

How to monitor 700 thermocouples? Rarback, Harvey

Navigate by Date:

Prev: Re: How to monitor 700 thermocouples? Ralph . Lange

Next: RE: An additional remark on C++ Jeff Hill

Index: 1994  1995  1996  1997  1998  1999  2000  <2001>  2002  2003  2004  2005  2006  2007  2008  2009  2010  2011  2012  2013  2014  2015  2016  2017  2018  2019  2020  2021  2022  2023  2024 

Navigate by Thread:

Prev: Re: How to monitor 700 thermocouples? Paul Sichta

Next: Re: How to monitor 700 thermocouples? Ralph . Lange

Index: 1994  1995  1996  1997  1998  1999  2000  <2001>  2002  2003  2004  2005  2006  2007  2008  2009  2010  2011  2012  2013  2014  2015  2016  2017  2018  2019  2020  2021  2022  2023  2024