Chapter 5 _______________________________________________  Wiring and Power Management
VAISALA_______________________________________________________________________ 39
CHAPTER 5
WIRING AND POWER MANAGEMENT
This chapter provides you with instructions on how to connect the 
power supply and the serial interfaces, and how to manage and estimate 
the average power consumption.
The WMT52 can be accessed through four different serial interfaces: 
RS-232, RS-485, RS-422 and SDI-12. Each of them can be wired either 
through the internal screw terminal or the 8-pin M12 connector 
(optional). Only one serial interface can be used at a time.
Power Supplies
Operating Voltage
Operating voltage Vin+: 5 ... 32 VDC
Notice that for the average current consumption, see the graphs in 
Figure 19 on page 40. The minimum consumption graph is for SDI-12 
standby mode.
The input power supply needs to be capable to deliver 60 mA (at 12 V) 
or 100 mA (at 6 V) instant current spikes with duration of 30 ms. These 
CAUTION
The cable openings in the sensor bottom assembly are covered with 
hexagonal rubber plugs. If you are not using the cable glands (included 
in the Bushing and Grounding Kit), keep the openings covered.