Installation, Operating & Maintenance Instructions
Series 650 DN 100-
250 (I.D. 4“ - 10”), DeviceNet
VAT Vakuumventile AG, CH-9469 Haag, Switzerland
Tel +41 81 771 61 61 Fax +41 81 771 48 30 [email protected] www.vatvalve.com
266341ED
2012-07-13
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3.10.1 Pressure control operation with 2 sensors
[applicable with 650 . . - . . .
Q
- . . . . version only]
If 2 sensor operation is enabled, changeover between the sensors is done automatically during pressure control. For
configuration refer to chapter «Setup procedure». We recommend a ratio of 10:1 between the pressure gauges. Max. ratio
is 100:1. High range respectively low range pressure gauge may be either connected to sensor 1 or sensor 2 input.
It‟s required to do correct sensor configuration.
Between 90 and 100% of the low range sensor full scale, the low range sensor is phased out while high range sensor is
phased in during pressure rise. During pressure decrease the high range sensor is phased out while low range sensor is
phased in. This maintains a functional response behavior in case of small calibration errors between the two sensors. The
PRESSURE output in this range is a blend between both sensors.
For monitoring purpose each sensor signal may be read out individually. Refer to «Explicit messaging inquiry commands
SENSOR 1 READING and SENSOR 2 READING».
Note:
Make sure that both sensors are calibrated.
Note:
Do not close optional gauge isolation valves during the transition phase between the sensors.
