Andy,

Is there a driver control board in there somewhere for those valves? 
If it has switches for manual/automatic control, is it possible that 
one of those switches has been bumped or otherwise changed position?

Paul Eby
Alberta Research Council


At 01:21 PM 14/05/2009, you wrote:
>The answer to the 4 VDC is...it spikes to 12 VDC to move the 
>solenoid then is held at 4 VDC to keep it open. Answer courtesy LRG. 
>Perhaps a faulty valve then. Anybody else having valve issues?
>
>andy
>
>
>
>  Andrew Schauer
>Earth and Space Sciences
>University of Washington
>Seattle, WA 98195
>
>
>206.543.6327
>[log in to unmask]
>http://depts.washington.edu/isolab/
>
>
>
>----- Original Message ----
>From: Andrew Schauer <[log in to unmask]>
>To: [log in to unmask]
>Sent: Thursday, May 14, 2009 12:20:12 PM
>Subject: [ISOGEOCHEM] LGR DLT-100
>
>Hi all,
>
>We have sent our DLT-100 liquid instrument back to LGR a few times 
>claiming water quantity problems. Each time, the two valves that 
>control nitrogen purge gas or vacuum pump are replaced. I suspected 
>our valves again due to recent water quantity problems and opened it 
>up to take a look. I have found the switch board that allows one to 
>control the valves manually and have determined that the valve on 
>the vacuum pump side does not function regularly but the nitrogen 
>purge gas valve does. I find our NResearch Standard 2-way normally 
>closed valves are 12 VDC and yet the instrument is only giving them 
>4 VDC. Does anyone with this instrument know if they either have 
>lower voltage valves or a power supply that is providing 12 VDC? Thank you.
>
>andy
>
>Andrew Schauer
>Earth and Space Sciences
>University of Washington
>Seattle, WA 98195
>
>
>206.543.6327
>[log in to unmask]
>http://depts.washington.edu/isolab/