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HE 5712 Operating Instructions
# 372048 | Version 1.4
7.4
Differential-pressure measurement
Differential Pressure Measurement Connections (HE 5712 Compact)
Pressure connections on the control unit (HE 5712 Modular)
The differential pressure is measured internally and transmitted as 4... 20 mA signal to the
higher-level controller or to an indicating device.
The current output is scalable over the adjustable measuring range.
For example:
0 … 30 mbar
≙
4
… 20 mA, 0 … 20 mbar
≙
4
… 20 mA
In normal operation, the cleaning process is started when the upper "Cleaning" threshold is
exceeded and stopped again when the lower "Cleaning" threshold is reached.
When the precoating function is activated, the cleaning starts at the upper threshold increased
by the precoating offset.
There is a delay time of 5 minutes to carry out post-cleaning during a normal shutdown
procedure without triggering an alarm signal by falling below the low alarm. The post-cleaning
threshold must be reached before the end of these 5 minutes, otherwise the low alarm will be
triggered.
p+
(raw gas)
p-
(Pure gas)
p+
(raw gas)
p-
(Pure gas)
