General Purpose Controller


The SZ1143b is a microprocessor-based general
purpose controller designed for use in a wide variety
of applications: general control, remote setpoint
control, general input reset ratio control and
differential input (i.e. temperature, pressure,
humidity, etc.) control.


• Stand-alone or network operation
• Two 4 to 20 mA analog inputs suitable for a broad
variety of transducers
• Two digital inputs for switches, alarms, clocks,
• One 4-20 mA modulating output
• Two relay outputs
• One relay output configurable to work with analog
input one or two
• Adjustable P+I+D control on modulating output
• Adjustable offsets and differentials on relay
• Application sequences include:
• Humidification
• Dehumidification
• Dew Point Control
• Differential Temperature
• Differential Pressure
• Static Pressure
• Hot or Chilled Water
• Hot or Chilled Water Reset

Call to order:


Specs & Docs


Accuracy: +/- 0.5%
Programming: EIA RS485 interface
Display: 32-character LCD
Communications: RS485, half duplex
Memory backup: Non-volatile EEPROM, no battery required
Operating temperature: 32 to 131°F (0 to 55°C)
Operating humidity: 0 to 100% RH, non-condensing
Storage temperature: 14 to 140°F (-10 to 60°C)

Supply voltage: 24 VAC +/- 20%
Inputs: Two 4-20 mA analog and two digital (dry contact)
Outputs: One 4-20 mA DC analog and two digital (SPST dry contact, 24 VAC @ 1 A)
Analog input impedance: 250Ω
Max. load resistance (analog output): 600Ω
Common mode rejection: 100 db @ 60 Hz
Power consumption: 5 VA max.

Specifications subject to change without notice.