WATLOWCompact Loop System, Providing Powerful Control in a 1 /8 DIN Package

Watlow’s SERIES CLS200 is a powerful line of controllers, 

combining performance and flexibility with compact design. 

The 4, 8 and 16 loop versions provide complete controller 

solutions for a broad range of applications. Support for 

multiple types of sensor inputs is available, including 

thermocouples, RTDs, linear voltage, current and frequency. 

Each controller can operate as a stand-alone system, and 

includes built-in serial communications for computer interface 

and data acquisition. Optional programmable ramp and soak 

features allow complex batch processing and sequencing. 

An enhanced feature option offers cascade control, ratio 

control, differential control, process variable retransmit and 

remote analog set point.

The SERIES CLS200 controllers are UL® and C-UL® listed and 

meet the requirements of the European Community EMC 

Directive and carry the CE mark.

Features and Benefits

PID control of up to 16 heat and cool loops

• Minimizes panel space per loop 

• Reduces installation time

• Increases reliability: fewer parts means fewer failures

Auto-tune

• Requires less time tuning

• Achieves excellent control with less expertise

Menu-guided operation with full text display

• Allows quick setup of the controller

• Simplifies operation

Eight jobs stored and recalled

• Changes quickly from one process to another

Multiple and mixed inputs

• Accepts combinations of thermocouples, RTDs, linear 

dc voltage and linear dc current sensors

• Reduces learning curve and inventory

Sensor failure detection

• Reduces time troubleshooting reversed, shorted and 

open sensors

High/low process and deviation alarms for each input

• Integrates as needed to integrate with PLC and other 

control elements

34 digital outputs

• Provides flexible configuration

• Allows use of outputs as needed for control and alarms

EIA/TIA-232 and 485 communications

• Connects to software for easy configuration and operation

• Allows integration with controllers and software

DAC and SDAC Modules

The optional DAC and SDAC modules are available for

Watlow SERIES CLS200 controllers.

DAC

The DAC (digital to analog converter) converts one or two 

of the controller’s distributed zero crossing (DZC) output 

signals to analog signals. Each output is field configurable 

for 4-20mA(dc), 0-5VDC or 0-10VDC.

SDAC

The SDAC (serial digital to analog converter) converts 

one controller output to a precise analog voltage or 

current signal. The unit is typically used for process variable 

retransmit, open-loop control, motor or belt speed control, 

or phase-angle fired SCR power controllers. The SDAC bears 

the CE mark and is UL® and C-UL® listed.

Firmware Options

Choose firmware with the features needed for the 

application:

• Standard—includes closed-loop PID control, auto-tune, 

alarms, job memory and failed sensor detection.

• Ramp and soak—includes the standard firmware 

features with the addition of ramp and soak and process 

variable retransmit. Each channel can be configured for 

standard PID control or ramp and soak operation. Unused 

control outputs on any channel can be configured for 

retransmition.

• Enhanced features— includes the standard firmware 

features with the addition of process variable retransmit, 

remote analog set point, cascade control, ratio control 

and differential control algorithms. Each channel can be 

configured for standard PID controller or one of the other 

control algorithms. Each channel of cascade control or 

remote analog set point requires two controller channels. 

Unused control outputs on any channel can be 

configured for retransmit.

Because the SERIES CLS200 has no onboard analog 

outputs, applications that use process variable retransmit 

typically require one SDAC module per retransmitted 

signal.

CLS200 Specifications

Operator Interface

• 32-character vacuum fluorescent display 

• 8-key keypad to access guided menus and prompts, 

enter passkey sequence, set values, switch between 

single channel and multiple channel displays

• Controller configuration can be loaded through the 

standard serial port

Analog Inputs

• CLS204 4 differential

• CLS208 8 differential

• CLS216 16 single-ended 

Noise Rejection 

• 120dB at 60Hz

Temperature Coefficient 

• 40ppm/°C 

Sensors/Inputs

• Thermocouples: user-selectable type, direct connection, 

linearization, reference junction compensation, reversed 

and shorted thermocouple detection and upscale break 

protection with output averaging 

• RTD: (CLS204 and CLS208 only) 2- or 3-wire, platinum, 

100Ω @ 0°C, DIN 0.003850Ω/Ω/°C curve, user-selectable 

range. Two user-selectable ranges offer different 

resolutions. Requires scaling resistors. See special/linear 

inputs in ordering information.

• Linear: current and voltage signals from linear transmitters 

• Pulse input

Input Range and Accuracy 

Sensor Range (°F) Range (°C) Accuracy

Type B 150 to 3200°F 66 to 1760°C ±4.0°C

Type E -328 to 1448°F -200 to 787°C ±1.0°C

Type J -350 to 1400°F -212 to 760°C ±1.2°C

Type K -450 to 2500°F -268 to 1371°C ±1.3°C

Type R 0 to 3210°F -18 to 1766°C ±2.8°C

Type S 0 to 3200°F -18 to 1760°C ±2.8°C

Type T -450 to 750°F -268 to 399°C ±1.6°C

RTDs available on CLS204 and CLS208 only.

Sensor Range (°F) Range (°C) Accuracy

RTD1 -148 to 527˚F -100 to 275˚C ±1.1˚C

RTD2 -184 to 1544˚F -120 to 840˚C ±1.6˚C

Note: Accuracy @ 25˚C ambient. Valid for 10 to 100 percent 

of span except Type B, which is specified for 800˚F to 

3200˚F. RTD is for 100 percent of span.

Linear Voltage and Current Inputs

Requires scaling resistors. See special inputs in ordering 

information.

0-20mA(dc)/4-20mA(dc)

0-5VDC

0-10VDC

Other ranges available. Contact factory. 

Pulse Input 

• One TTL-level square wave input up to 2kHz

Input Sampling Rate at 60Hz 

Each channel has the following scans per second:

• CLS204: 6 samples per second (update time: 0.167 sec.)

• CLS208: 3 samples per second, (update time: 0.333 sec.)

• CLS216: 1.5 samples per second, (update time: 0.667 sec.)

Internal Measurement Resolution

• 0.006 percent, greater than 14 bits

Calibration

• Automatic zero and full scale

Digital Inputs 

• TTL-level used for selecting recipes or jobs, or R/S triggers

• 8 inputs and 1 pulse input with 50-pin terminal board 

option

• 2 inputs and pulse input or 3 inputs with 18-pin terminal 

block option

Digital Outputs

• 34 digital outputs are available with 50-pin terminal 

board option

• 10 control outputs with 18-pin terminal block option

• 1 or 2 control outputs are user assigned for each loop

• Each control output can be configured for on-off time 

proportioning, or distributed zero crossing

• Outputs sink up to 60mA each at 5VDC

• 350mA at 5VDC available from on-board supply 

Alarm Outputs 

• Independent process and deviation alarms for each 

channel

• Alarms can operate any output not used for control

• User-programmable deadband, delay and startup 

suppression

• Global alarm output activates when any alarm occurs

• Watchdog output indicates controller is functioning 

correctly

Serial Interface 

• EIA/TIA-232 or EIA/TIA-485 

Baud Rate

• 2400, 9600 or 19200, user-selectable

Communications Protocols

• Form of ANSI X3.28-1976, (D1, F1) compatible with 

Allen-Bradley PLC/2

• Modbus® RTU

Line Voltage/Power

• 15 to 24VDC ± 3VDC @ 1A (max.),

300mA (no load)

Agency Approvals

• UL®, C-UL® listed: UL®61010-1 safety requirements for 

measurement, control and laboratory equipment

• CE Mark: See Declaration of Conformity for details