Vaisala WAT12 - Manual (Page 22)

User's Guide ________________________________________________________
20 _____________________________________________________M210309EN-A
Figure 12 below illustrates wiring for high noise
environment. It is essential to ground the cable also at the
power supply.
0206-050
Figure 12 Wiring for High Noise Environment
Figure 13 below illustrates wiring for long distance with the
5 mA loop current. Note the maximum resistance values for
both the power and signal leads.
0206-051
Figure 13 Long Distance Wiring
Figure 14 on page 21 illustrates 4-wire wiring for long
distance with a 48 VDC power supply.
CAUTION A source resistance, over 1000Ω, must be used for
dropping VIN to an acceptable level, because if VIN
exceeds 28 VDC, the transmitter may be damaged
permanently.