Hach 51 Series User Manual page 11

Connections to electronic boards
Potential Instrument Damage. Delicate internal electronic components can be damaged by static electricity,
resulting in degraded performance or eventual failure.
Note: Any loose connection wires should be bundled tightly together with the use of nylon cable ties.
Sensor cable
An ORBISPHERE cable (10 wire shielded, Part N° 32505.mm) is needed to connect the sensor(s) to
the instrument. The instruments have a Lemo 10 socket on the back panel where the sensor cable
has to be connected.
Electronic boards connectors
Connectors P8 on the main board
to Measurement board
either side of the connector and pull it out securely. Perform all connections with these connectors
unplugged. Once finished, attach the connectors to the boards by pushing them firmly in place
(levers up).
Main board
Figure 4 Main board
Connector P8
The numbers listed below refer to the 13 available P8 connections (from left to right) in
1. RS-485 (signal A)
2. RS-485 (signal B)
3. PROFIBUS-DP (GND)
4. PROFIBUS-DP (+ 5 V)
5. PROFIBUS-DP (signal -)
6. PROFIBUS-DP (signal +)
7. PROFIBUS-DP (signal RTS)
Connector P3
Ethernet RJ 45. Connect the instrument to the local network by passing an ethernet cable through
the ethernet cable gland (refer to
P3 connector illustrated in
N O T I C E
(Figure 4 on page 11) and J7 on the measurement board (refer
on page 12) are made of two parts. Push down carefully the black levers on
Instrument connections
Figure 4.
Figure 5 Connector P8
8. Not used
9. Not used
10. Not used
11. System alarm relay (N.O.)
12. System alarm relay (N.C.)
13. System alarm relay (Common)
on page 9) and connecting to the
Figure 5.
English 11