ES-1813 Rev.2
18TK
Rack-mounted DCS Signal Conditioners 18-RACK
THERMOCOUPLE CONVERTER
(fast response)
Functions & Features
• Accepting direct input from a thermocouple and providing two standard process signals
• 5-segment linearization
• Burnout protection
• High-accuracy cold junction compensation
• Second channel output available at the front terminals and at the Standard Rack connector
• Fast response type
Typical Applications
• High-accuracy cold junction compensation benefits narrow span measurements
• 0.1 μA burnout sensing enables long distance transmission with minimum offset drifts
• Electric furnace (isolation)
• No burnout type can connect to a single T/C in parallel with a recorder
MODEL: 18TK–[1]6[2]–R[3]
ORDERING INFORMATION
• Code number: 18TK-[1]6[2]-R[3]
Specify a code from below for each of [1] through [3].
(e.g. 18TK-266-R/BL)
• Temperature range (e.g. 0 – 800°C)
[1] INPUT THERMOCOUPLE
1
: (PR) (Usable Range 0 to 1760°C, 32 to 3200°F)
2
: K (CA) (Usable range -270 to +1370°C, -454 to +2498°F)
3
: E (CRC) (Usable range -270 to +1000°C, -454 to +1832°F)
4
: J (IC) (Usable range -210 to +1200°C, -346 to +2192°F)
5
: T (CC) (Usable range -270 to +400°C, -454 to +752°F)
6
: B (RH) (Usable range 0 to 1820°C, 32 to 3308°F)
7
: R (Usable range -50 to +1760°C, -58 to +3200°F)
8
: S (Usable range -50 to +1760°C, -58 to +3200°F)
N
: N (Usable range -270 to +1300°C, -454 to +2372°F)
0
: Specify
OUTPUT 1
Voltage
6
: 1 – 5 V DC (Load resistance 2000 Ω min.)
[2] OUTPUT 2
Current
A
: 4 – 20 mA DC (Load resistance 600 Ω max.)
Voltage
6
: 1 – 5 V DC (Load resistance 2000 Ω min.)
POWER INPUT
DC Power
R
: 24 V DC
(Operational voltage range 24 V ±10 %, ripple 10 %p-p max.)
[3] OPTIONS
Burnout
blank
: Upscale burnout
/BL
: Downscale burnout
/BN
: No burnout
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 1
: Connector
Output 2
: 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 1 to output 2 to power
Overrange output
: Approx. -10 to +120 % at 1 – 5 V
Zero adjustment
: -5 to +5 % (front)
Span adjustment
: 95 to 105 % (front)
Linearization
: Standard
Cold junction compensation
: CJC sensor attached to the
input terminals
INPUT SPECIFICATIONS
Input resistance
: 20 kΩ minimum
Burnout sensing
: 0.1 μA
Minimum span
: 3 mV
Offset:
Max. 1.5 times span
Minimum span (in °C)
(PR)
: 370°C
K (CA)
: 75°C
E (CRC)
: 50°C
J (IC)
: 60°C
T (CC)
: 75°C
B (RH)
: 780°C
R
: 360°C
S
: 380°C
N
: 110°C
Minimum span (in °F)
(PR)
: 670°F
K (CA)
: 140°F
E (CRC)
: 90°F
J (IC)
: 110°F
T (CC)
: 140°F
B (RH)
: 1410°F
R
: 650°F
S
: 690°F
N
: 200°F
For the temperatures that range below 0°C, the transmitter
may partially not satisfy the described accuracy. Consult
factory.
INSTALLATION
Current consumption
: Approx. 35 mA with voltage output
Approx. 65 mA with current output
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
: ±0.4 % (at over 400°C or 750°F for R, S and PR; over 770°C or 1420°F for B)
Cold junction compensation error
(at 20°C ±10°C or 68°F ±18°F)
K, E, J, T, N
: ±0.5°C or ±0.9°F
S, R, PR
: ±1°C or ±1.8°F
Temp. coefficient
: ±0.015 %/°C (±0.008 %/°F)
(at over 400°C or 750°F for R, S and PR; over 770°C or 1420°F for B)
Response time
: Approx. 25 msec. (0 – 90 %)
Burnout response
: ≤ 10 sec.
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 1 or output 2 or power)
500 V AC @ 1 minute
(output 1 to output 2 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