20
16.3
AMD limit switch maintenance
16.3.1 Electrical verification
Check that the voltage at the ter and - is over 7.5 V when the vane is in the slot.
Connect a multimeter with the scale in DC mA, in series with the te.
Verify that the current is less than 1 mA when the vane is into the slot and more than 3 mA
when the vane is out of the slot.
The verification can be done with the following circuit diagram:
Without the sensor, the operation of the amplifier can be checked using the following circuit
diagram:
With the potentiometer the current through the NAMUR amplifier can be modified. The
switching point must be between 1.2 mA and 2.1 mA. That is, with the current below 1.2
mA the output relay must have a state and above 2.1 mA the output relay must have the
other state.
16.4 TH6
transmitter
maintenance
No special maintenance is required.
9V battery
(nominal 8.2V
for NAMUR)
NAMUR
amplifier
Potentiometer
Summary of Contents for AD Series
Page 28: ...28 22 ATEX CERTIFICATE ...
Page 29: ...29 ...
Page 30: ...30 ...
Page 31: ...31 23 DECLARATIONS OF CONFORMITY ACCORDING TO ATEX ...