Measuring inputs und additional channels
With option RHA the measuring instrument also incorporates a digital sensor
for temperature, humidity, and atmospheric pressure (2), occupying channels
M01 to M31.
However, in wireless transmission to a subsequent linked device, only four
channels can be transmitted, normally the first four (M00 to M30 or M00 to
M11). If channels are deleted or deactivated other configurations are also
possible. (see 11.1.1).
On the measuring instruments this gives the following channel assignment:
9.3 Potential separation
When organizing a properly functioning measuring setup it is very important to
ensure that no equalizing current can flow between sensors, power supply, and
peripherals. All points must therefore lie at the same potential and / or any un-
equal potentials that do exist must be electrically isolated.
Sensors combined within one connector and sensors with their own power
supply are electrically interconnected and must therefore be operated in isolati-
on. The voltage at the measuring inputs themselves (between B, C, D and A
or - ) must not exceed 5 volts.
The power supply is isolated by means of the transformer in the mains adapter
or, for DC operation, by means of a DC/DC converter (OA2490-U or ZA2690-
UK).
ALMEMO
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