Interlock problem

Kai Zang kaizang at
Tue Oct 16 09:07:49 PDT 2012

Hi Julie,

Thanks for your suggestion. I tried restarting software and computer, enable and disable but it is not work. I also checked probe and changed two of them but they are not working as well. Before I can clear the error message, but this time it jumps out every time. ><"


Electrical Engineering
Stanford University

----- Original Message -----
From: "Julie Segal" <jsegal at>
To: "John Shott" <shott at>, "Kai Zang" <kaizang at>
Cc: "micromanipulator6000" <micromanipulator6000 at>
Sent: Tuesday, October 16, 2012 8:55:12 AM
Subject: RE: Interlock problem

I have noticed that sometimes the B1500 gives the message even when you are not trying to go above 42V.  Usually you can clear it (I think there is an "OK" button or something in the message) and go on, but sometimes you have to re-start the analysis software.
- Julie
From: John Shott [shott at]
Sent: Tuesday, October 16, 2012 7:30 AM
To: Kai Zang
Cc: micromanipulator6000
Subject: Re: Interlock problem


What voltage were you trying to use?  The B1500 has an external
interlock cable that won't allow SMU voltages to exceed +/- 42 V unless
the interlock is closed.  I only realized this recently ... Julie Segal
pointed this out to me ...

We have ordered parts to attach magnetic proximity switches to the cover
of the probe station so that the interlock will be satisfied when the
probe station is closed (or mostly closed).  Unfortunately, while most
of those parts will be shipped to us in the next couple of days, one of
them won't arrive until the first week of Novemeber.

Were you trying to apply voltages higher than 42V, or were you seeing
this error under all circumstances?



On 10/15/2012 10:18 PM, Kai Zang wrote:
> Hi all,
> Has any one of you encountered a problem of interlock problem? It said 'Interlock circuit is open. Interlock circuit must be closed for setting voltage source/compliance absolute value exceeding 42V'. And we cannot conduct any measurements at all.
> Thanks for your help in advance! =)
> Best,
> Kai
> -----
> Kai ZANG
> Electrical Engineering
> Stanford University

More information about the micromanipulator6000 mailing list