Test The Control Loop / Ai0; Test The Transmitter Loop / Ao0 - Val Controls IHP24 Troubleshooting Manual

If the difference is less 100:
1. Verify that the position sensor is connected to the actuator
If the difference is less 1500:
1. Increase signal span from the sensor: See sensor manual
The difference between the Open ADC value and the 50% ADC value shall be approximately equal
to the difference between the Close ADC value and 50% ADC value.
1. Check the signal from the position sensor

2.3 Test the control loop / AI0

Send 4mA followed by a 20mA signal from DCS or a loop calibrator
Push Status 1.Live status and push down arrow down until SP-mA is shown.
From DCS or loop calibrator
4mA
20mA
If signals are 0 mA
1. Check wiring
If 4 mA and 20 mA signals are "off"
1. Perform a signal calibration of AI0/Control loop: See IHP24 manual

2.4 Test the transmitter loop / AO0

Verify that the position signal transmitted from the IHP24 and the position signal received by DCS
or loop calibrator are identical
Push Status 1.Live status and push down arrow down until TM-mA is shown.
IHP24 Live menu - TM-mA
If TM-mA is 3.5 mA
1. Verify that there are no errors in the error log
If 0 mA is received by DCS or loop calibrator
1. Check wiring
1. Check if the sensor is active or passive. AO0 is for use of passive transmitters, i.e. output is
active: See IHP24 manual
Val Controls A/S  Limfjordsvej 3  DK-6715 Esbjerg N  Tel. +45 7547 0600  Fax +45 7547 0611
DHP-UM-026
Revision: 2
IHP24 Live menu - SP-mA
Readout from DCS or loop calibrator
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