AMALGAMATED INSTRUMENT RM3-SW-LPN Guide

RM3-SW-LPN & RM3-SW-LPI
Slidewire Input Transmitters
Operation and
Instruction Manual

Introduction
This manual covers the installation and operation of models RM3-SW-LPN (non isolated) and RM3-SW-LPI
(isolated). These models accepts 3 wire slidewire inputs (1kΩto 1MΩ) and provide 4-20mA loop powered
outputs. These models are available with one, two, three or four input/output channels. Reverse polarity and
over current protection is provided on the output of each channel. A LED indicator is provided for each
channel. The brightness of the LED will vary with output level, 20mA giving the brightest output.
Zero & span adjustment is via front panel potentiometers marked Z and S.
Mechanical Installation
The RM3 clips onto a standard 35mm DIN rail as shown below.
Dimensions
Page 2 of 7 RM3SWMAN-1.1-0
Earth bolt may be slid in from the rear
of the instrument (top or bottom)
44mm
91mm
135mm

Electrical Installation
Plug in type screw connector terminal blocks are provided for ease of installation. The terminal blocks allow
for wires of up to 1.5mm2to be fitted. Connect the wires to the appropriate terminals as indicated in the
diagram below, connections for a 4 channel instrument are shown. The RM3-SW-LPN and RM3-SW-LPI
models have the same wiring connections. A case earth lug which can be placed at the top or bottom of the
instrument is provided.
Excitation for the slidewire is provided internally by the RM3-SW. It is essential that only a passive slidewire
input is used i.e. do not use a sensor with external excitation.
Data label example (located on instrument case)
Page 3 of 7 RM3SWMAN-1.1-0
4
5
4
5
2
3
5
4
S
Z
Z
O/P
S
Z
S
S
Z
3
2
1
3
1
1
1
2
2
3
4
5
4-20mA Output
4-20mA Output
4-20mA Output
4-20mA Output
+
+
+
+
-
-
-
-
RM3
SERIES
AMALGAMATED INSTRUMENT CO
O/P
O/P O/P Channel 1
Channel 2
Channel 3
Channel 4
Common
Common
Excitation +
Common
Wiper
Wiper
Wiper
Wiper
Excitation +
Excitation +
Common
Excitation +
Earth lug - can be located at the top or
bottom of the case as required
RM3-SW-LPN-4 SERIAL No :
4 CHANNELS
1 SLIDEWIRE EXC +VE
2 SLIDEWIRE WPR
3 SLIDEWIRE COM
4 4-20mA OUTPUT +VE
5 4-20mA OUTPUT -VE

Typical interconnection diagram - loop powered
Page 4 of 7 RM3SWMAN-1.1-0
24VDC
IN+
IN-
Case earth
RM3 PLC
4-20mA
3
2
1
EXC
+VE
WPR
COM
4
5
Case earth
RM3
4
5IN+
IN-
External
power
supply
4-20mA
24VDC
+
-
Output
3
2
1
EXC
+VE
WPR
COM
Typical interconnection diagram - externally powered

Zero and Span Adjustment
Each channel is individually adjustable for zero and span. Adjustment is via front panel potentiometers
marked Z (zero) and S (span). The procedure for zero and span adjustment is given below.
1. Attach a milliammeter and power supply to the output terminals as shown below.
2. Attach the slidewire and place it in its zero position. Adjust the zero potentiometer until the
milliammeter shows a reading of 4mA (or 4.0 etc.). If a 4mA output is not achievable then
adjustment to the slidewire linkage position may be required. The RM3 requires that at the 4mA
end the mechanical position of the wiper is at, or very close to (within 20% of full travel), zero.
3. Move the slidewire wiper to its full scale position. Adjust the span potentiometer until the
milliammeter shows a reading of 20mA (or 20.00 etc.).
Note: If it is not possible to input the exact value for 20mA then input a value corresponding to an
output of as close to 20mA as you can and adjust the span potentiometer until the required mA
output for this input is reached. The span adjustment allows the 20mA output to be placed
anywhere in the range from 60% to 100% of the slidewire full scale travel.
Typical Zero and Span adjustment setup
Page 5 of 7 RM3SWMAN-1.1-0
+
+
-
-
Slidewire
Milliammeter 24V
Loop Supply
4
5
4
5
2
3
5
4
S
Z
Z
O/P
S
Z
S
S
Z
3
2
1
3
1
1
1
2
2
3
4
5
RM3
SERIES
AMALGAMATED INSTRUMENT CO
O/P
O/P O/P

Specifications
TECHNICAL SPECIFICATIONS
Input: 3 wire slidewire 1kΩto 1MΩfull range values
Output: 4-20mA (RM3-SW-LPN is non isolated, RM3-SW-LPI is isolated)
Zero & span: Zero within 20% of zero position
Span between 60% to 100% of full scale position
Supply: Output - Loop powered. Loop supply required 15 to 34VDC nominal.
Supplies should be regulated and filtered.
Accuracy: Better than 0.1% of full scale when calibrated
Linearity: Better than 0.1 % of full scale when calibrated
Response Time: 0.5 sec to 1%
Protection: Reverse polarity and over current output protection
Maximum Load: RL= Supply (V) - 9 Ohms
0.02
Load Effects: Effect on accuracy of changing load resistance is no greater than 0.1%
of full scale
Ambient temp: 0 to 60°C
Humidity: 5 to 95% non condensing
PHYSICAL CHARACTERISTICS
Case size: 44mm x 91mm x 135mm
Mounting: 35mm DIN Rail mount (EN50022)
Connections: Plug in screw terminals (max 1.5mm2wire)
Weight: 230 gms for single channel
250 gms for dual channel
300 gms for three channel
320 gms for four channel
Specifications are subject to change without notice
Page 6 of 7 RM3SWMAN-1.1-0

Guarantee & Service
The product supplied with this manual is guaranteed against faulty workmanship for a period of 2
years from the date of dispatch.
Our obligation assumed under this guarantee is limited to the replacement of parts which, by our
examination, are proved to be defective and have not been misused, carelessly handled, defaced or
damaged due to incorrect installation. This guarantee is VOID where the unit has been opened, tampered
with or if repairs have been made or attempted by anyone except an authorised representative of the
manufacturing company.
Products for attention under guarantee (unless otherwise agreed) must be returned to the
manufacturer freight paid and, if accepted for free repair, will be returned to the customers address in
Australia free of charge.
When returning the product for service or repair a full description of the fault and the mode of
operation used when the product failed must be given.
In any event the manufacturer has no other obligation or liability beyond replacement or repair of
this product.
Modifications may be made to any existing or future models of the unit as it may deem necessary without
incurring any obligation to incorporate such modifications in units previously sold or to which this guarantee
may relate.
Page 7 of 7 RM3SWMAN-1.1-0
This document is the property of
the instrument manufacturer
and may not be reproduced in whole or part without the
written consent of the manufacturer.
This product is designed and manufactured in Australia.