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Troubleshooting
General
Troubleshooting the QuadScan II can be accomplished by isolating the CPU/power supply boards or the
display/function assembly. In most cases, the problem will be isolated to a sensor or transmitter failure.
Reference the appropriate transmitter manual for specific transmitter troubleshooting procedures. If the
problem exists in the receiver/controller and not the sensor or transmitter, then determine if the problem is
common to all channels or just a specific channel. The following procedure can be used to help isolate
the problem area.
CAUTION: CORRECTIVE DEVICES CONNECTED TO THE ALARM RELAY
CONTACTS MUST BE DISABLED BEFOR PERFORMING THE FOLLOWING TESTS.
Channel Test Setup
1.
Remove the cover plate located on the lower bottom section of the enclosure.
2.
Identify the Channel 1 current loop input wires located on TB1 and disconnect. The Fail LED
will illuminate and the fail common relay will activate (change state). The internal horn will not
activate.
3.
Connect a current generator with a range of 0 to 20 mA, (observe correct polarity), to the (+) IN
and (–) IN terminals on TBI. The fail LED will extinguish and the fail relay will return to normal.
For additional details on the testing procedure, refer to System Maintenance.
Refer to Table 2 for additional help in isolating or locating the malfunction.
Once the problem area has been diagnosed, because of the complexity of the circuit board design, all
repairs should be limited to interchanging circuit boards. Circuit boards are available as spare parts or
can be purchased as required from Scott Health & Safety.
Summary of Contents for QuadScan II 7400
Page 10: ...5 of 116 Quick Start Programming Menu Tree...
Page 20: ...15 of 116 Figure 5 Mounting Dimensions of Model 7400...
Page 24: ...19 of 116 Figure 9 Battery Backup P N 096 0719 Outline Interconnection Wiring...
Page 60: ...55 of 116 Figure 13 Interconnect Wiring Between 7400 Remote Relay Assembly...