Lambrecht sun[e] 00.16130.501030, Руководство пользователя

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4.4 Electrical connection of sun[e]: wiring diagram
The instrument must be powered by an external power supply, providing an operating voltage in the
range from 8 to 30 VDC. This is the main power supply for the sensor, using the brown and white
wires. Do not put more than 30 Volt across these wires, this will damage the sensor.
Table 4.4.1 Wiring diagram of sun[e]
PIN WIRE
00.16130.501030
Modbus over RS-485
1 Brown VDC [+]
2 White
VDC [−]
3 Blue RS-485 B / B’ [+]
4 Black RS-
485 A / A’[−]
5 Grey not connected
Shield mesh shield
Note 1: At the connector-end of the cable, the shield is connected to the connector housing.
Figure 4.4.1 : Connector layout of sun[e], indicating PIN numbers (viewed from cable side)
4.5 Grounding and use of the shield
Grounding and shield use are the responsibility of the user. The cable shield (called shield in the
wiring diagram) is connected to the aluminium instrument body via the connector. In most situations,
the instrument will be screwed on a mounting platform that is locally grounded. In these cases the
shield at the cable end should not be connected at all. When a ground connection is not obtained
through the instrument body, for instance in laboratory experiments, the shield should be connected to
the local ground at the cable end. This is typically the ground or low voltage of the power supply or the
common of the network. In exceptional cases, for instance when both the instrument and a datalogger
are connected to a small size mast, the local ground at the mounting platform is the same as the
network ground. In such cases ground connection may be made both to the instrument body and to
the shield at the cable end.
4.6 Connecting to an RS-485 network
sun[e] is designed for a two-wire (half-duplex) RS-485 network. In such a network, sun[e] acts as a
slave, receiving data requests from the master. An example of the connection to an RS-485 two-wire
network is shown in the figure below. sun[e] is powered from 8 to 30 VDC. The power supply is not
shown in the figure. The VDC [-] power supply ground must be connected to the common line of the
network. [
Modbus over serial line specification and implementation guide V1.02 ( www.modbus.org ). ]
After the last nodes in the network, on both sides, line termination resistors (LT) are required to
eliminate reflections in the network. According to the RS-485 standard, these LT have a typical value
of 120 to 150 Ω. Never place more than two LT on the network and never place the LT on a derivation