Instruction Manual
D102748X012
DLC3010 Digital Level Controller
Installation
May 2018
25
Power/Current Loop Connections
Use ordinary copper wire of sufficient size to ensure that the voltage across the digital level controller terminals does
not go below 12.0 volts DC. Connect the current signal leads as shown in figure 2‐9. After making connections,
recheck the polarity and correctness of connections, then turn the power on.
RTD Connections
An RTD that senses process temperatures may be connected to the digital level controller. This permits the instrument
to automatically make specific gravity corrections for temperature changes. For best results, locate the RTD as close to
the displacer as practical. For optimum EMC performance, use shielded wire no longer than 3 meters (9.8 feet) to
connect the RTD. Connect only one end of the shield. Connect the shield to either the internal ground connection in
the instrument terminal box or to the RTD thermowell. Wire the RTD to the digital level controller as follows (refer to
figure 2‐11):
Two‐Wire RTD Connections
1. Connect a jumper wire between the RS and R1 terminals in the terminal box.
2. Connect the RTD to the R1 and R2 terminals.
Note
During Manual Setup
,
you must specify the connecting wire resistance for a 2‐wire RTD. 250 feet of 16 AWG wire has a resistance
of 1 ohm.
Three‐Wire RTD Connections
1. Connect the 2 wires which are connected to the same end of the RTD to the RS and R1 terminals in the terminal
box. Usually these wires are the same color.
2. Connect the third wire to terminal R2. (The resistance measured between this wire and either wire connected to
terminal RS or R1 should read an equivalent resistance for the existing ambient temperature. Refer to the RTD
manufacturer's temperature to resistance conversion table.) Usually this wire is a different color from the wires
connected to the RS and R1 terminals.
Communication Connections
WARNING
Personal injury or property damage caused by fire or explosion may occur if this connection is attempted in an area which
contains a potentially explosive atmosphere or has been classified as hazardous. Confirm that area classification and
atmosphere conditions permit the safe removal of the terminal box cap before proceeding.
The Field Communicator interfaces with digital level controller from any wiring termination point in the 4–20 mA loop
(except across the power supply). If you choose to connect the HART communicating device directly to the
instrument, attach the device to the loop + and - terminals inside the terminal box to provide local communications
with the instrument.
