HBM MP85A - Incremental, SSI and DC Sensors

Electrical connection
MP85A A0293_06_E00_03 HBM: public 31
With sense leads, a broken wire is only detected and reported as a fault if this
occurs in both leads. This also means that if the connection is faulty (e.g. if the
feedback bridges are missing when full or half bridges are connected in a
4-wire configuration) an error message appears (display: Transducer error).
If a single sense lead is broken, only an increased measured value is
displayed.
5.5.3 Incremental, SSI and DC sensors
Fig. 5.7, on page 32, shows how these transducer models are connected in
incremental, SSI or DC sensor mode.
A supply voltage is available at screw terminals 5 and 6, pins 7 and 8 for
feeding incremental encoders, transducers with an SSI interface and sensors
with a voltage signal. You can select an internal or external power supply using
switch S1. To do this, open the device (see section 6) and – for an external
supply – set switch S1 to “24V external”.
S Transducer supplied from MP85A process controller:
Transducer supply voltage 5V "10%, 150mA max. (for both channels
together). In this case, the supply voltage is not electrically isolated from
the measurement system.
S Transducer supplied from an external power pack:
Connect a voltage between 10 … 30 V
DC
(24 V
DC
nominal), including
ground, to screw terminal 3, pins 5 and 6. A current of max. 300mA (for
both channels together) can then be drawn at screw terminals 5 and 6, pins
7 and 8.
This external supply voltage is electrically isolated from the measurement
ground and simultaneously supplies the digital control outputs.