Watlow Series CZR Solid State Relay

up to 42 amps
Watlow Series CZR Solid State Relay
The SERIES CZR solid state relay from Watlow® provides a low-cost, highly compact and versatile solid state option
for controlling electric heat. With DIN-rail and back panel mounting standard on every controller, the CZR allows for simple and quick installation.

The extensive capabilities of the SERIES CZR include single-phase, 18 to 42 ampere zero-cross switching up to 600VAC (see output rating curve). The unique integrated design removes the guesswork associated with selecting a proper heat sink and precise terminations for the application.

This controller holds many agency approvals and is ideal for applications that require UL®, CSA and CE approvals. The SERIES CZR is available in VAC/VDC input contactor versions. All configurations are model number dependent and factory selectable. SERIES CZR is reliably backed by a two-year warranty from Watlow

Watlow: Your Heat Solutions Resource Brochure (EN)
Watlow: Vos Solutions de Chauffage Brochure (FR)
Back to Watlow CZR Solid State Relay

Product Features

DIN-rail or standard panel mount
  • Provides versatile, quick and low-cost installation
Compact size
  • Reduces panel space and cost
Touch-safe terminals
  •  Increases installer and operator safety
Mercury free
  • Offers environmentally safe solution
Faster switching with solid state
  • Saves energy and extends heater life
UL® 508 recognized, CSA LR700195 certified and CE 60950
  • Assures safety
Back-to-back SCR design
  • Offers rugged design for different application environments

Product Specifications

Control Mode:
Zero-cross fired contactor output
Operator Interface:
  • Command signal input
  • Input signal indication LED
Input Command Signal:
  • Input Type DC1
  • Turn on voltage 4VDC max., turn off voltage 1VDC min.
  • Input current: dc typically 10mA @ 4VDC,13mA @ 32VDC
  • Input Type AC1
  • 90 to 140Vrms, must turn on at 90VAC, must turn off at 10VAC
  • Input current: 15mA typical @ 120VAC
Output Voltage:
  • 24; 24VAC min. to 280VAC max.
  • 48; 48VAC min. to 530VAC max.
  • Off state leakage 10mA at 77°F (25°C) max.
  • Holding current: 250mA max.
Agency Approvals:
  • Class II construction
  • UL® 508 recognition, File #E73741 and CSA File LR 700195
  • 206/95/EC CE Low Voltage Directive
Output Terminals:
  • Compression type
  • For 18A models:
  • Max. wire size 3.0 mm (10 AWG), torque to 0.6Nm (5.3 in. lbs)
  • For 24 to 42A models:
  • Max. wire size 16 mm (6 AWG stranded) torque to 1.5-1.7Nm (13-15 in. lbs)
Operating Environment:
  • Up to 176°F (80°C). See output rating curves for your application.
  • 0 to 90% RH (relative humidity), non-condensing
  • Insulation tested to 3,000 meters
  • Units are suitable for “pollution degree 2”
  • Cycle time should be less than 3 seconds
  • Options include DIN-rail or standard back panel mounting.
  • The DIN-rail specification: DIN EN 50022, 1.38 in. x 0.30 in. (35 mm x 7.5 mm)
  • Min. clipping distance: 1.37 in. (34.8 mm)
  • Max. clipping distance: 1.39 in. (35.3 mm)
  • Mount cooling fins vertical
  • 9.2 oz (260g)
  • 24 to 42A models: 3.95 in. (100 mm) high x 1.75 in. (45 mm) wide x 4.3 in. (109 mm) deep
  • 18A models: 3.95 in. (100 mm) high x 0.89 in. (22.6 mm) wide x 3.9 in. (99 mm) deep

Ordering information