Rockwell Automation 1769-HSC Compact High Speed Counter Module - Manual (Page 62)

62 Rockwell Automation Publication 1769-UM006E-EN-P - July 2013
Chapter 3 Installation and Wiring
Outputs
The four output terminals must be powered by a user-supplied external source.
User-power range is from 5…30V DC. See the Output Specifications in
Appendix A on
page 124 .
There is no isolation between the outputs, but the outputs are isolated from the
inputs and the 1769 Compact bus.
Electronic Protection
The electronic protection of the 1769-HSC module has been designed to
provide protection for current overload and short-circuit conditions. The
protection is based on a thermal cut-out principle. In the event of a short-circuit
or current overload condition on an output channel, that channel will turn off
within milliseconds after the thermal cut-out temperature has been reached.
Overcurrent Autoreset Operation
The module detects overcurrent situations and reports them to the backplane in
the Out
nOverCurrent bits of the input array. When the overcurrent condition is
detected, the outputs are turned off.
The module can latch outputs off to emulate the behavior of a physical fuse. Use
the OvercurrentLatchOff bit to enable or disable this feature. When the
OvercurrentLatchOff bit is set and an overcurrent situation occurs (even
momentarily) the physical output will be latched off until the ResetBlownFuse bit
is cycled from off to on (rising edge triggered). During the latched off time, the
Readback.
n bit in the input array also shows that the output is off.
If the OvercurrentLatchOff bit is not set, the output will be turned off for 1
second and then be retried (if still directed to be on). Retries will repeat until the
overcurrent situation is corrected.
The four physical outputs can be latched off only. The virtual outputs are
not affected.
IMPORTANT During the retry period, the physical output and the Readback.n bits will
be on briefly (until the overcurrent causes them to shut off again). Take
this into consideration and configure your
system accordingly.
TIP Correct short-circuit and overload conditions as soon as possible. If
short-circuit and overload conditions occur for extended periods, damage
can occur.