June 2016
6
Quick Start Guide
2.0 Connect wiring
Use the following steps to wire the transmitter:
1. Remove the electronics housing cover on the side marked FIELD TERMINALS.
2. Wire the RTD.
Temperature is input through the Resistance Temperature Detector (RTD)
probe and circuitry. The Rosemount 3095FC provides terminations for a 2- or
3-wire 100-ohm platinum RTD with a IEC 751 curve. The RTD has an alpha (
α
)
equal to 0.00385.
The RTD mounts directly to the piping using a thermowell. RTD wires should
be protected by a metal sheath or by a conduit connected to a conduit wiring
fitting on the enclosure. The RTD wires connect to the three screw terminals
designated “RTD” on the Termination Board.
Wiring between the RTD and Rosemount 3095FC should be shielded wire,
with the shield grounded only at one end to prevent ground loops. Ground
loops cause RTD input signal errors.
Table 2
displays the RTD terminal connections for the various RTD probes.
3. Wire the power supply.
The terminals are labeled CHG+ for positive power connection and CHG- for
negative power connection on a label on the termination board. These
connections provide the input voltage and power for the battery charging
circuit. The maximum voltage that can be applied to the CHG+/CHG-
terminals is 28 Volts dc.
4. Communications wiring
The Local Operator Interface (LOI) port provides direct communications
between the Rosemount 3095FC and the serial port of an operator interface
device, such as an IBM compatible PC using an EIA-232 (RS-232) link. The
interface allows access to the Rosemount 3095FC (using Rosemount User
Interface Software) for configuration and transfer of stored data.
Table 2. RTD Signal Routing
Terminal
Designation
3-wire RTD
2-wire RTD
RTD +
Signal positive input
RTD +
RTD +
RTD +
Signal positive input
RTD +
Jumper to RTD +
RTD RET
Return reference
RTD RET
RTD RET
Pin
Signal
Description
1
CHG+
Battery 8.0 to 28 V Power
2
CHG-
Battery Common
4832 Rev CA.fm Page 6 Wednesday, June 22, 2016 2:06 PM