ES-0431 Rev.1

18KYCH

Rack-mounted DCS Signal Conditioners 18K-RACK

CONTROL OUTPUT ISOLATOR

(applicable to HART signal, opencircuit detection selectable)
Functions & Features
• Takes 4 - 20 mA DC as input
• Isolates and relays HART signals
• Opencircuit detection selectable
• Module can be retracted without removing wiring for an insulation test
• Capable of monitoring input signals at front terminals
• Optional power switch

MODEL: 18KYCH–AA–R[1]

ORDERING INFORMATION

• Code number: 18KYCH-AA-R[1]
Specify a code from below for [1].
  (e.g. 18KYCH-AA-R/S/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 (multiple selections)

Power Switch
blank: None
/S: With power switch
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) and connector
  Power: 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)
With power switch: Selectable from the front
(factory default: ON)
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 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: 500 V AC @ 1 minute (input to output to power to ground )

EXTERNAL VIEW

EXTERNAL DIMENSIONS unit: mm [inch]

TERMINAL ASSIGNMENTS

SCHEMATIC CIRCUITRY & CONNECTION DIAGRAM