Powering The Transmitter - Emerson Rosemount 8712EM Quick Start Manual

November 2017
5.6

Powering the transmitter

The transmitter is available in three models. The AC powered transmitter is
designed to be powered by 90–250VAC (50/60Hz). The DC powered
transmitter is designed to be powered by 12–42VDC. The low power
transmitter is designed to be powered by 12–30VDC. Before connecting
power to the transmitter, be sure to have the proper power supply, conduit,
and other accessories. Wire the transmitter according to national, local, and
plant electrical requirements for the supply voltage.
If installing in a hazardous location, verify that the meter has the appropriate
hazardous area approval. Each meter has a hazardous area approval tag
attached to the side of the transmitter housing.
AC power supply requirements
Units powered by 90 - 250VAC have the following power requirements. Peak
inrush is 35.7A at 250VAC supply, lasting approximately 1ms. Inrush for other
supply voltages can be estimated with: Inrush (Amps) = Supply (Volts) / 7.0
Figure 5-9:
0.24
0.22
0.20
A
0.18
0.16
0.14
0.12
A. Supply current (amps)
B. Power supply (VAC)
Quick Start Guide
AC current requirements
90 110 130 150 170 190
B
Quick Start Guide
210 230 250
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