Johnson Controls System 350 A350A Technical Bulletin

A350A/B Electronic Temperature Control
The A350A/B Series is an on/off electronic
temperature control with a Single-Pole, Double-Throw
(SPDT) relay output and a Light-Emitting Diode (LED)
relay status indicator. Designed to operate with both
heating and cooling equipment, this control includes an
adjustable differential and an interchangeable
temperature sensor.
As are all System 350™ products, the A350A/B is
housed in a NEMA 1, high-impact plastic enclosure.
The modular design provides easy, plug-together
connections for quick installation and future
expandability.
❑ Modular Design
❑ ❑ ❑ ❑ Plug-together Connectors
and 35 mm DIN Rail
Mounting
❑ Two Standard Models
Cover Wide Setpoint
Ranges
-30 to 130°F (-34 to 55°C) or
90 to 250°F (32 to 121°C)
❑ Wide Adjustable Differential
of 1 to 30F° (0.6 to 16.7C°)
❑ ❑ ❑ ❑ Field-Selectable Mode
Jumpers
❑ ❑ ❑ ❑ Available with Either
External or Concealed
Setpoint
❑ ❑ ❑ ❑ Interchangeable
Temperature Sensors
© 1999 Johnson Controls, Inc.
Part No. 24-7664-44, Rev. C
Code No. LIT-930010
System 350™
Features and Benefits
Enables stage, display, and power modules to
be purchased and installed as needed
Eliminates wiring between modules and
reduces installation costs
Reduces inventory by encompassing
temperature ranges required to support the
majority of Heating, Ventilation, Air
Conditioning, and Refrigeration (HVAC/R)
applications
Enables the user to match equipment cycle
rate and/or sequencing for a given application
Operates in both heating and cooling
applications
Helps deter accidental and unauthorized
adjustments
Increases versatility and serviceability
FANs 930, 930.5, 125, 121
Product/Technical Bulletin A350
Figure 1: A350 Series Electronic
Temperature Control
Issue Date 0899
1
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