Operational Error Status Register Set - Lakeshore 642 User Manual

5.1.4.3.2

Operational Error Status Register Set

The Operational Error Status Register reports the following instrument operational error events: remote enable fault
detected, power supply flow switch fault detected, magnet flow switch fault detected, high line voltage, low line voltage,
temperature high, external current program error, calibration error. Any or all of these events may be reported in the
standard event summary bit through the enable register, see Figure 5-5. The Operational Error Status Register is the
second value of the two values associated with the Error Status Registers. The Error Status Enable command (ERSTE)
programs the enable register and the query command (ERSTE?) reads it. ERSTR? reads and clears the Error Status
Register. The used bits of the Error Status Event Register are described as follows:
Remote Enable Fault Detected (REF), Bit (7) – This bit is set if a fault condition is detected on the remote enable
interlock.
Power Supply Flow Switch Fault Detected (PFF), Bit (6) – This bit is set if a fault condition is detected on the power
supply flow switch interlock.
Magnet Flow Switch Fault Detected (MFF), Bit (5) – This bit is set if a fault condition is detected on the magnet flow
switch interlock.
High Line Voltage (HLV), Bit (4) – This bit is set if the power line voltage exceeds an acceptable amplitude. Operation
can continue but additional heat may be dissipated by the instrument.
Low Line Voltage (LLV), Bit (3) – This bit is set if the power line voltage drops below an acceptable amplitude.
Operation can continue but output voltage may not reach maximum specification.
Temperature High (OOV), Bit (2) – This bit is set if the internal temperature of the instrument exceeded 40 °C. The
output current will be set to zero and will not be settable until the fault is cleared.
External Current Program Error (EPE), Bit (1) – This bit is set if the instrument cannot go into external or sum
current programming modes because the programming voltage is too high. The output current will be set to zero and
will not be settable until the fault is cleared.
Calibration Error (CAL), Bit (0) – This bit is set if the instrument is not calibrated or the calibration data has been
corrupted.
Error Status
7
Condition Register
REF PFF
ERST?
Error Status
7
Event Register
REF PFF
ERSTR?
Error Status
7
Enable Register
REF PFF
ERSTE, ERSTE?
Computer Interface Operation
Lake Shore Model 642 Electromagnet Power Supply User's Manual
6 5 4 3 2
MFF HLV LLV TH
6 5 4 3 2
MFF HLV LLV TH
AND
AND
AND
AND
AND
5
6 4 3 2
MFF HLV LLV TH
Figure 5-5. Operational Error Status Register
1 0 Bit
EPE CAL Name
1 0 Bit
EPE CAL Name
AND
AND
AND
1 0 Bit
EPE CAL Name
OR
To Bit 1 (OESB) of
Status Byte Register
(See Figure 5-1.)
5-11