ES-1819 Rev.10
18SN
Rack-mounted DCS Signal Conditioners 18-RACK
INPUT LOOP POWERED ISOLATOR
Functions & Features
• Loop-powered design eliminates output loop power supply
• 500 V DC input-to-output isolation
• 350 Ω output drive with 4 – 20 mA
Typical Applications
• Isolation between control room and field instrumentation, between telemetering system and input device
• Eliminates ground problems in existing systems thanks to easiness of application without requiring additional power wiring
MODEL: 18SN–[1][2]0
ORDERING INFORMATION
• Code number: 18SN-[1][2]0
Specify a code from below for each of [1] and [2].
(e.g. 18SN-A60)
[1] INPUT
Current
A
: 4 – 20 mA DC
H
: 10 – 50 mA DC
[2] OUTPUT 1
Current
A
: 4 – 20 mA DC
Voltage
6
: 1 – 5 V DC
OUTPUT 2
0
: None
GENERAL SPECIFICATIONS
Construction
: Rack-mounted; terminal access via screw terminals on the front and connector on the rear; terminal cover provided
Connection
Input
: M3.5 screw terminals (torque 0.8 N·m)
Output
: M3.5 screw terminals (torque 0.8 N·m) and connector
Screw terminal
: Nickel-plated steel
Isolation
: Input to output
Zero adjustment (front)
Voltage output
: -5 to +5 %
Current output
: -0.5 to +0.5 %
Span adjustment (front)
Voltage output
: 95 to 105 %
Current output
: 98.5 to 101.5 %
INPUT & OUTPUT
■ Input 4 – 20 mA DC / Output 1 – 5 V DC
Equivalent input impedance
: Approx. 250 Ω with 20 mA input
Operational range
: 3 – 22 mA DC
(Accuracy is assured within 4 – 22 mA)
Load resistance
: ≥ 50 kΩ
■ Input 10 – 50 mA DC / Output 1 – 5 V DC
Equivalent input impedance
: Approx. 100 Ω with 50 mA input
Operational range
: 7 – 55 mA DC
(Accuracy is assured within 8 – 55 mA)
Load resistance
: ≥ 50 kΩ
■ Input 4 – 20 mA DC / Output 4 – 20 mA DC
Equivalent input impedance
: 230 Ω plus load resistance with 20 mA input
Operational range
: 3 – 22 mA DC
(Accuracy is assured within 4 – 22 mA)
Load resistance
: 50 – 350 Ω (min. 50 Ω required for adequate operation)
■ Input 10 – 50 mA DC / Output 4 – 20 mA DC
Equivalent input impedance
: 90 Ω + [load resistance×0.16] with 50 mA input
Operational range
: 7 – 55 mA DC
(Accuracy is assured within 8 – 55 mA)
Load resistance
: 50 – 600 Ω (min. 50 Ω required for adequate operation)
•INPUT 4 – 20 mA DC / OUTPUT 1 – 5 V DC
•INPUT 10 – 50 mA DC / OUTPUT 1 – 5 V DC
•INPUT 4 – 20mA DC / OUTPUT 4 – 20 mA DC
•INPUT 10 – 50 mA DC / OUTPUT 4 – 20 mA DC
INSTALLATION
Operating temperature
: -5 to +55°C (23 to 131°F)
Operating humidity
: 30 to 90 %RH (non-condensing)
Mounting
: Standard Rack 18BXx or 18KBXx
Weight
: 150 g (0.33 lb)
PERFORMANCE in percentage of span
Accuracy
: ±0.1 %
Temp. coefficient
Voltage output
: ±0.015 %/°C (±0.008 %/°F)
Current output
: ±0.02 %/°C (±0.01 %/°F)
Response time
Voltage output
: ≤ 0.5 sec. (0 – 90 %)
Current output
4 - 20 mA DC input
: Approx. 45 msec. (0 – 90 %, 50 Ω load)
10 - 50 mA DC input
: Approx. 15 msec. (0 – 90 %, 50 Ω
load)
Load effect (current output)
4 – 20 mA input
: 0.015 %/Ω (50 – 150 Ω)
0.003 %/Ω (150 – 350 Ω)
10 – 50 mA input
: 0.015 %/Ω (50 – 100 Ω)
0.003 %/Ω (100 – 600 Ω)
(The unit is calibrated with 250 Ω load at the factory.)
Insulation resistance
: ≥ 100 MΩ with 500 V DC
Dielectric strength
: 500 V AC @ 1 minute
(input to output)
1500 V AC @ 1 minute
(input or output to ground)
EXTERNAL DIMENSIONS unit: mm [inch]
TERMINAL ASSIGNMENTS
SCHEMATIC CIRCUITRY & CONNECTION DIAGRAM