ES-1769 Rev.4
18AS2
Rack-mounted DCS Signal Conditioners 18-RACK
DC ALARM
Functions & Features
• Providing relay contact closures at preset DC input levels
• Single or dual (Hi/Lo) trip
• Frontaccessed screwdriver setpoint adjustments
• Enclosed relays
Typical Applications
• Annunciator
• Various alarm applications
MODEL: 18AS2–[1][2]–R
ORDERING INFORMATION
• Code number: 18AS2-[1][2]-R
Specify a code from below for each of [1] and [2].
(e.g. 18AS2-62-R)
• Special input range (For code 0)
Use Ordering Information Sheet (No. ESU-1033) to specify alarm output code 0 specifications.
[1] INPUT
Current
A
: 4 – 20 mA DC (Input resistance 250 Ω)
D
: 0 – 20 mA DC (Input resistance 50 Ω)
G
: 0 – 1 mA DC (Input resistance 1000 Ω)
H
: 10 – 50 mA DC (Input resistance 100 Ω)
Voltage
3
: 0 – 1 V DC (Input resistance 1 MΩ min.)
4
: 0 – 10 V DC (Input resistance 1 MΩ min.)
5
: 0 – 5 V DC (Input resistance 1 MΩ min.)
6
: 1 – 5 V DC (Input resistance 1 MΩ min.)
0
: Specify voltage (See INPUT SPECIFICATIONS)
[2] ALARM OUTPUT
1
: Hi (coil energized at alarm)
2
: Hi (coil de-energized at alarm)
3
: Lo (coil energized at alarm)
4
: Lo (coil de-energized at alarm)
5
: Hi/Lo; N.O., OFF in power failure
(connector output not available)
6
: Hi/Lo; N.C., OFF in power failure
(connector output not available)
0
: Specify
POWER INPUT
DC Power
R
: 24 V DC
(Operational voltage range 24 V ±10 %, ripple 10 %p-p max.)
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)
Alarm output
: M3.5 screw terminals (torque 0.8 N·m) and connector
Power input
: Supplied from connector
Screw terminal
: Nickel-plated steel
Isolation
: Input to output to power
Relay
: Enclosed
Setpoint adjustments
: Multi-turn screwdriver adjustments (front); -5 – +105 % independently
Hysteresis (deadband)
: Approx. 1 %
Front LEDs
: Red LED turns on when the coil is energized.
INPUT SPECIFICATIONS
■
DC Current
: Input resistor incorporated
■
DC Voltage:
0 – 300 V DC
Minimum span:
1 V
Offset:
Max. 1.5 times span
Input resistance:
≥ 1 MΩ
OUTPUT SPECIFICATIONS
Output
: Enclosed SPST and SPDT relays
Rating
:
30 V DC @ 1 A (resistive load)
0.2 A for the connector output
Maximum switching voltage
: 30 V DC
Max. switching power
: 30 W (6 W for the connector output)
Minimum load
: 5 V DC @ 10m A
Mechanical life
: 5 × 10
7
cycles
INSTALLATION
Current consumption
: Approx. 80 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
: 150 g (0.33 lb)
PERFORMANCE in percentage of span
Trip point repeatability
: ±0.1 %
Temp. coefficient
: ±0.015 %/°C (±0.008 %/°F)
Response time
: ≤ 0.5 sec. (0 – 100 % at 90 % setpoint)
Line voltage effect
: ±0.1 % over voltage range
Insulation resistance
: ≥ 100 MΩ with 500 V DC
Dielectric strength
: 1500 V AC @ 1 minute
(input to output or power)
500 V AC @ 1 minute (output to power)
1500 V AC @ 1 minute (input or output or power to ground)
EXTERNAL VIEW
EXTERNAL DIMENSIONS unit: mm [inch]
TERMINAL ASSIGNMENTS
SCHEMATIC CIRCUITRY & CONNECTION DIAGRAM