Omega Products CN2508-R1 User Manual

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⁄8 DIN Temperature/Process

Limit Controllers

CN2508 Series

FM

APPROVED

U Dual Display
U Universal Input
U High/Low Limit
U Limit Relay Output (Fixed)
U Additional Modular Outputs (Optional)
U RS485 (Optional)
U Remote reset (Optional)

The CN2508 Series is part of a range of new
generation series of limit controllers that incorporate
numerous product specification, communication,
display interface and software improvements that
surpass competitive limit device offerings in ease of
use and programming.

By adding more versatile features and user-friendly
functionality like digital inputs, an easy-to-use HMI,
jumperless and auto-hardware configuration,
24 Vdc transmitter power supply and MODBUS
communication across the range, the CN2508 limit
controller transform the complicated into the simple
while saving you time (as much as 50% on product
set-up), reducing inventory stock and virtually
eliminating the likelihood of operator errors.

The CN2508 limit controllers are affordable, well­featured, easy to use and adaptable with performance
features that work for you to make limit control simple.

The CN2508 is a fail-safe protection device to prevent
damage to equipment or products. It will shut down a
process when a preset temperature is reached and
cannot be reset by the operator until the process has
returned to a safe condition.

SPECIFICATIONS

Environmental Characteristics

Operating Temperature: 32 to 131°F (0 to 55°C)
Storage Temperature: -4 to 176°F (-20 to 80°C)
Humidity: 20 to 95% non-condensing RH

Electrical

Supply Voltage: 100 to 240V, 50/60 Hz, optional 20 to 48 Vac

50/60 Hz or 22 to 65 Vdc

Power Consumption: 5 W/7.5 VA maximum

Inputs

Thermocouples: J, T, K, L, N, B, R, S, C; Pt Rh 20%

vs. Pt 40% Rh

RTD: 3-wire, PT100 DC linear (scalable -1999 to +9999)
Volts: 0 to 5V, 1 to 5V, 0 to 10V, 2 to 10V
DC Milliamps: 0 to 20 mA or 4 to 20 mA
DC Millivolts: 0 to 50 mV, 10 to 50 mV

®

OUTPUTS

Output 1: (Limit relay) fixed
Outputs 2 and 3: (Alarm relay) are user-selectable and

customized based on desired application

Choose From the Following Output Types
Max # of Outputs: 3 for alarm, 24 Vdc transmitter power

supply or retransmit of process value/limit trip setpoint
Limit Relay: SPDT; 240 Vac, 5 A resistive; lifetime

>100,000 operations at rated voltage/current

Alarm Relay: Optional SPDT; 240 Vac, 2 A resistive;

lifetime >500,000 operations at rated voltage/current

SSR Drive (Optional Drive Capability): >10 Vdc nominal

into 500 Ω minimum

DC Linear: Optional 0 to 20 mA, 4 to 20 mA into 500 Ω

max; 0 to 10V, 1 to 5V, 2 to 10V, 0 to 5V into 500 Ω min;
outputs have 2% over/under drive applied; accuracy
±0.25% (mA into 250 Ω load, V into 2k Ω load); degrading
linearity to ±0.5% for increasing burden to specified limits

Triac: Optional 0.01 to 1A AC, 20 to 280 Vrms,

47 to 63 Hz (limit 2)

Transmitter Power Supply: Optional 24 Vdc (limit 1)

Output Functions

Process Alarm: Reverse or direct
Modes (Alarm 1 and 2): High/low, band, deviation,

logical OR/AND

Retransmit: Process value or limit setpoint

CN2508 shown
actual size.

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Electrical Performance

Accuracy: ±0.1% of input range ±1 LSD

(thermocouple CJC better than 1°C)

Input Sample Rate: 4 per second, 14-bit resolution
Impedance: >10M Ω for the thermocouple and mV ranges,

47 kΩ for V ranges and 5 Ω for mA ranges
Sensor Break Detection: <2 seconds (except zero based

DC ranges), limit output opens, low alarms activate for RTD,
mA or V ranges

Communications Interface

User-Selectable: 2-wire, RS485 serial communications

option with choice of MODBUS RTU or ASCII protocol;
1200 to 19200 baud

PC Configuration: Offline configuration from serial port to
dedicated configuration socket (comms option not required)

Protection

IEC IP66 (NEMA 4X): Front panel
IEC IP20: Behind the panel protection

Dimensions

Panel Cutout: 45 W x 92 mm H (1.77 x 3.62")
Height: 96 mm (3.77")
Width: 48 mm (1.89")
Depth: 100 mm (3.94")
Weight: 0.21 kg (0.46 lb)
Mounting: Plug in panel with fixing strap

Input Types Range

-200 to 1373°C
(-328 to 1399°F)

0 to 761°C
(32 to 1401°F)

-200 to 262°C
(-328 to 503°F)

0 to 1399°C
(32 to 2550°F)

0 to 1650°C
(32 to 3002°F)

0 to 1649°C
(32 to 3000°F)

100 to 1824°C
(211 to 3315°F)

0 to 762°C
(32 to 1403°F)

0 to 2320°C
(32 to 4208°F)

Pt 100 RTD (0.00385)

(-328 to 1472°F)

-199 to 800°C

0 to 20 mA, 4 to 20 mA -1999 to 9999
0 to 10 Vdc, 0 to 5 Vdc,

0 to 50 mVdc

SM

OMEGACARESM extended warranty program is
available for models shown on this page. Ask
your sales representative for full details when

Extended Warranty

Program

placing an order. OMEGACARE
labor and equivalent loaners.

-1999 to 9999

SM

covers parts,

To Order Visit omega.com/cn2504 for Pricing and Details

Model No. Description

CN2508-R1 Single output, relay
CN2516-R1-LV Single output, relay, low voltage

Output and Communications Options (Field Installable Modules)
Model No. Description

Output 2 and 3 Slot

2500X-R Relay module
2500X-DC DC pulse module
2300X-F2 Linear DC module
2500X-T Triac module (output 2 only)
2300X-TPS Transmitter power supply (output 3 only)
Option A Slot
2300X-485 RS485 communications
2300X-DI Digital input

Accessories (Field Installable)

Model No. Description

CN2500-SOFT Configuration software
CNQUENCHARC Noise suppression kit, 110 to 230 Vac

Comes complete with mounting bracket and operator’s manual.

Ordering Example: CN2508-R1, single output controller and operator’s manual.
OCW-2, OMEGACARE

SM

extends standard 3-year warranty to a total of 5 years.

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