Validate Cm Operation - Ametek Drexelbrook Universal IV CM Installation And Operating Instructions Manual

Universal IV™ CM Density Compensated Model
2.4

Validate CM Operation

2.4.1 Verify the capacitance values on the CM and DCM match
1. If they do not match, you should see a "HART 5 CRITICAL COMM LOSS
FAILURE "on the DCM. To clear this , power cycle the CM only by removing
the 4-20mA leads on the CM for 10 seconds then replace them.
If the capacitance values are still mismatched, it is likely a faulty cut monitor
(CM) transmitter. Contact Drexelbrook Service department.
2.4.2 Verify matching capacitance values are appropriate for the application.
(A) While powered, remove CM
transmitter from back board. If
the CAP value changes on the
tramsitter the transmitter is fine.,
go to (B).
If the CAP value remains fixed,
power cycle the CM transmitter
and restart the CAP check. If the
value continues to remain locked,
replace the CM transmitter.
(B) While connected, remove the
probe from the system. Touch the
outside of the probe, if the CAP
value doesn't change on the CM,
replace the probe and the cable.
2.4.3 If you have an expected value from the center column, the CM is operating
normally in current conditions. Proceed to the next section 2.5 Modbus
Validation
<14pF
Problem
14-40 pF
Confirm Scenario
15
>40 pF
Problem
(A) Remove CM transmitter.
L i f t p r o b e l e a d s f r o m t h e
backboard. Ohm check probe
ground (GND) and verify it is not
shorted. If it is not OPEN, verify
probe install. (Insure probe is
plumb and not angled and hitting
the wall of the pipe.
(B) While connected, remove
probe from the install; if CAP
value drops sharply, then the
probe was shorted. Check the
probe installation.