From shott at stanford.edu  Wed Dec  5 13:05:14 2012
From: shott at stanford.edu (John Shott)
Date: Wed, 05 Dec 2012 13:05:14 -0800
Subject: Measurements above 42 volts ...
Message-ID: <50BFB70A.1050208@stanford.edu>

Micromanipulator 6000 Community:

Several of you have noticed that the Agilent B1500 limits measurements 
to +/- 42 volts even though the SMUs are capable of supplying up to +/- 
100 volts.

There is an interlock circuit on the back of the B1500 that is supposed 
to be connected to switches that prevent voltages higher than 42 volts 
from being applied unless protective enclosures are in place.  I've 
learned that most other places using a B1500 have simply shorted out the 
interlock switch at the back of the unit.

We have installed a pair of magnetic proximity switches in the probe 
station enclosure so that the interlock will be happy (that is the 
switches are closed) when the copper cover on the probe station is fully 
down.  As a result those of you needing to apply voltages greater than 
42 volts can no do so if you simply fully close the cover of the probe 
station enclosure.

Please let me know if you have any questions,

John