HP 6038A - Page 43

3-224 in Figure 3-18. the FLT output is used to trigger a
relay driver circuit. When the driver circuit energizes the relay,
the power supply is disconnected from the load. This applic-
tion is useful to provide protection for the load if the controller
is halted during a debugging session and a fault condition arises.
Once the controller is no longer busy, the fault line can be reset
by rading the fault register and the power supply can be in¬
itialized to its power on state (see Table 3-6) by sending a CLR.
3-225 The setup in Figure 3-19a chains the FLT output of
one supply to the INH input of the next. In this case a fault
condition in any of the supplies would cause all of the supplies
to be disabled simultaneously without controller involvement
or external circuitry. The controller can be made aware of the
fault via a service request (SRQ). Sending a FAULT? and then
a RST, will restore the output of the supply's to their program¬
med values before the INH circuit was tripped. Sending a CLR
will initialize the supply to its power on state (see Table 3-6).
To provide proper operation, correct polarity must be obseved
when connecting external circuitry to the INH input. A typical
example is shown in Figure 3-19b.