EST EST3X - Signature Loop Controller Troubleshooting

Chapter 7: Service and troubleshooting
210 EST3X Technical Reference Manual
model of the known good device using the 3-SDU or replace the substituted
device with a model that matches the suspect device.
3. If the substituted device is preprogrammed with a different device address, a
trouble occurs at the address of the suspect device because it was removed.
The system may also generate a device trouble if the substituted device
address matches another device already configured on the loop or it may
generate an “unprogrammed device” trouble. You must remove the
substituted device, and then use the SIGA-PRO tool or the 3-SDU to
reprogram its address to remove the fault.
Signature loop controller troubleshooting
Table 61 provides a list of possible problems that may be detected by the loop
controller module. For information on identifying and locating Signature data loop
problems, refer to “Using the SDU Signature Series diagnostics tool” on page
213.
Table 61: Signature Series loop controller troubleshooting
Problem
Possible cause
A
n open is detected on the loop • The loop is incorrectly wired or a connector is loose
• A detector or isolator base is defective
• A conductor is broken
• A device is not installed on the loop
• A device is not defined in the 3-SDU
A short is detected on the loop
• The loop is incorrectly wired (often crossed wi
res on a
device base)
• A detector, detector base, or module is defective
• The insulation between conductors is nicked
A ground fault is detected on the loop
• There is a pinched wire between the device and
electrical box
• The wire insulation is nicked