
Document: LT0273
MX4428 MXP Engineering / Technical Manual
Device
Processing
Issue 1.5
24 March 2006
Page 9-13
9.8.4
SUPPLY MONITORING - DIM800
The DIM800 supply is monitored with input AI3 of the device ASIC. If the supply voltage is
less than 18V, a SUPPLY FAIL fault is generated. (The threshold can be changed with
parameter 3 if needed.) If the supply fails completely, a DIM800 with revision less than 10
will stop responding to polls and a NODE FAIL fault is generated.
9.9
RIM
PROCESSING
9.9.1 POSITION
MONITORING
Correct Relay state
DI0
Condition
0 OK
Not activated
1 Relay
Stuck
0 Relay
Stuck
Activated
1 OK
Changes in these states are verified as described in section 9.22. Verified faults
representing a “relay stuck” condition are logged as CONTROL CB FAIL at the MX4428,
with the return to normal event logged as CONTROL CB NML.
9.10
SNM
PROCESSING
9.10.1 PROGRAMMING
Supply Monitoring Required
DO6
No 1
Yes 0
9.10.2 SUPPLY
FAULT
DETERMINATION
Input AI1
Condition
AI1 > P3
Supply Fault
AI1 <= P3
Supply OK
Note that Parameter 3 cannot reliably be adjusted to monitor supplies of different voltages.
9.10.3
EOL AND POSITION MONITORING
Correct Relay Position
AI0
Condition
P1 < AI0 <= 255
Open circuit fault
P2 <= AI0 <= P1
Normal
0 <= AI0 < P2
Short circuit fault
Not activated
Any No
Position
Fault
Any
No Open Circuit Fault
No Short Circuit Fault
P1 <= AI0 < 255
No Relay Stuck Fault
Activated
0 <= AI0 < P1
Relay Stuck Fault
Changes in these states are verified as described in section 9.22.