Vaisala DMT340 - Manual (Page 61)

Chapter 3 ________________________________________________________________ Installation
VAISALA ________________________________________________________________________ 59
0503-037
Figure 40 Relay Module
The numbers refer to Figure 40 above:
1 = Indication led for the relay 1 or 3
2 = Relay test buttons
3 = Flat cable pins
4 = Indication led for relay 2 or 4
WARNING The relay module may contain dangerous voltages even if the
transmitter power has been disconnected. Before working on the relay
module you must switch off both the transmitter and the voltage
connected to the relay terminals.
WARNING Do not connect the mains power to relay unit without grounding the
transmitter.