ES-1833 Rev.1
18YCH
Rack-mounted DCS Signal Conditioners 18-RACK
CONTROL OUTPUT ISOLATOR
(applicable to HART signal, opencircuit detection selectable)
Functions & Features
• Accepting a 4 – 20 mA DC input and providing an isolated 4 – 20 mA DC output
• Input from the Standard Rack connector can be monitored at the front terminals
• Isolates and relays HART signals
• Opencircuit detection selectable
MODEL: 18YCH–AA–R[1]
ORDERING INFORMATION
• Code number: 18YCH-AA-R[1]
Specify a code from below for [1].
(e.g. 18YCH-AA-R/B)
INPUT
Current
A
: 4 - 20 mA DC (Input resistance approx. 250Ω)
OUTPUT
Current
A
: 4 – 20 mA DC (Load resistance 600 Ω max.)
250 Ω ±10 % for HART communication
POWER INPUT
DC Power
R
: 24 V DC
(Operational voltage range 24 V ±10 %, ripple 10 %p-p max.)
[1] OPTIONS
Opencircuit detection
blank
: none
/B
: Opencircuit detector
GENERAL SPECIFICATIONS
Construction
: Rack-mounted; terminal access via screw terminals on the front and connector on the rear; terminal cover provided
Connection
Input
: Connector
Input monitor
: M3.5 screw terminals (torque 0.8 N·m)
Output
: M3.5 screw terminals (torque 0.8 N·m)
Power input
: Supplied from connector
Screw terminal
: Nickel-plated steel
Isolation
: Input to output to power
Zero adjustment
: -5 to +5 % (front)
Span adjustment
: 95 to 105 % (front)
Opencircuit detection
: Input current 0 mA when the output loop is open.
Photo MOSFET Relay ON Resistance; 3 Ω max.
INPUT SPECIFICATIONS
■
DC Current
: Input resistor incorporated
Input current
: ≥ 0 mA
OUTPUT SPECIFICATIONS
The output goes below 0 % when the input is open.
HART COMMUNICATION
Transmission gain
: Approx. -3 dB (within 1 – 3 kHz)
measured with 250 Ω at output
Loop impedance
: 250 Ω ±10 %
Communication directions
: Bidirectional
INSTALLATION
Current consumption
: Approx. 60 mA
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
: 110 g (0.24 lb)
PERFORMANCE in percentage of span
Accuracy
: ±0.1 %
Temp. coefficient
: ±0.015 %/°C (±0.008 %/°F)
Response time
: ≤ 0.5 sec. (0 – 90 %)
Line voltage effect
: ±0.1 % over voltage range
Insulation resistance
: ≥ 100 MΩ with 500 V DC
Dielectric strength
: 1500 V AC @ 1 minute
(output to input or power)
500 V AC @ 1 minute (input to power)
1500 V AC @ 1 minute
(input or output or power to ground)
EXTERNAL DIMENSIONS unit: mm [inch]
TERMINAL ASSIGNMENTS
SCHEMATIC CIRCUITRY & CONNECTION DIAGRAM