38
C
HAPTER 6:
Service
6.2.2 Existing Installation No Longer Working
1. Power the instrument off, then on again to see if it is a soft failure.
2. Power the computer off, then on again to see if communication port
is locked up.
3. Check all cable connections.
4. Check that the com port assignment has not been changed. In Mic-
rosoft Windows®, the com port number can be checked using
Device
Manager
under
Ports
(COM & LPT).
5. Check that the USB driver is installed properly and that the device is
functioning. In Microsoft Windows®, the device status can be
checked using Device Manager by right-clicking
Lake Shore Model
121 Current Source
under
Ports
(COM & LPT) or
Other Devices
and
then clicking Properties.
6.2.3 Intermittent Lockups
1. Check cable connections and length.
2. Increase the delay between all commands to 100 ms to make sure
the instrument is not being overloaded.
3. Ensure that the USB cable is not unplugged and that the Model 121
is not powered down while the com port is open. The USB driver cre-
ates a com port when the USB connection is detected, and removes
the com port when the USB connection is no longer detected.
Removing the com port while in use by software can cause the soft-
ware to lock up or crash.
Summary of Contents for 121
Page 6: ......
Page 10: ...iv ...
Page 46: ...36 CHAPTER 5 Options and Accessories ...
Page 54: ...44 CHAPTER 6 Service ...
Page 60: ...50 APPENDICES B 1 1 CE Declaration for Model 121 ...
Page 61: ...51 B 1 2 CE Declaration for the Power Supply Part Number 109 132 ...
Page 62: ...52 APPENDICES ...