Electrical Installation; Connecting The Cable(S) To The Transmitter - Emerson Rosemount 3101 Quick Start Manual

September 2018

Electrical installation

5.0

Connecting the cable(s) to the transmitter

The Rosemount 3100 Series is a two-wire loop-powered transmitter accepting
power supplies as follows:
The 3101: 12 to 30 Vdc

The 3102: 12 to 40 Vdc

The 3105: 12 to 40 Vdc (non-hazardous area), 12 to 30 Vdc (hazardous area)

Note
To comply with the CSA approval requirements, the Rosemount 3101 and

3102 must be powered from a Rosemount 3490 Series Control Unit or a class
2 separate extra-low voltage (SELV) source.
Other devices may reset if connecting the transmitter to a multi-drop system

while the loop is powered. De-energize the loop to avoid devices being reset.
Each transmitter is supplied with two cable entries. A suitable conduit system or
cable gland must be used to maintain the weather-proof rating and hazardous
area protection. Any unused entry must be sealed with a suitably rated blanking
plug.
A two-core, shielded/screened cable is required for external power supply and
output signal connections. The cable is not supplied.
5.1 Hazardous area installation (Rosemount 3105 only)
When the Rosemount 3105 is used with a Rosemount 3490 Series Control Unit,
no additional safety barriers are required. If powering the Rosemount 3105 from
any other source, ensure a suitable Intrinsically Safe (IS) barrier is fitted in the
non-hazardous (safe) area.
The barrier must be chosen such that its output parameters Uo, Io and Po are
less than Ui, Ii and Pi of the transmitter.
IS parameters: Ui = 30 V, li = 120 mA, Pi = 0.82 W, Li = 108 mH, Ci = 0 nF
The sum of the capacitance and the inductance of the transmitter and the
connecting cable must not exceed the maximum specified for the barrier
chosen.
5.2 Connect the cable(s) to the transmitter
1. Make sure that the power supply is disconnected.
2. Undo the three cover screws and then lift the transmitter housing cover.
The cover on the metal housing can rest on the hinge. Place an object under
the cover to avoid the transmitter toppling over.
3. Pass the cable through the cable gland/conduit.
Quick Start Guide
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