DESCRIPTION AND OPERATION
LOGIC POWER
I-E96-316A
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LOGIC POWER
Logic power (+5 VDC and
±
15 VDC) drives the QRS circuits. It
connects through the top 12-pin card edge connector (P1)
shown in Figure
. P3 su24 VDC to operate the ana-
log output circuits.
BUS FAULT TIMER
The bus fault timer is a one-shot timer that is reset by the slave
expander bus clock; the MFP generates the bus clock. If the
bus clock stops (indicating a MFP error or failure), the bus
fault timer
times out
in 10 milliseconds. This disables the digi-
tal outputs and sets the analog outputs to their default values
(set by dipswitches S2 and S3). A red front panel status LED
indicates a bus fault (
time-out
).
STATUS LED INDICATOR
A front panel module status LED indicator shows the operating
state of the QRS. Circuits on the QRS determine the module
status and light the LED.
explains corrective actions to take.
