Barton Instruments Model 322C Blind Switch
Model 322C Blind Switch
The Model 322C is a blind SPDT,
snap-acting switch designed
for use in hazardous areas. An
optional two-switch configuration
is available. The Model 322C
provides a highly repeatable alarm
signal capable of performing electrically controlled system
functions for liquid level and flow applications.
The switch is adjustable to open (normally closed) or close
(normally open) on either increasing or decreasing DP and
is positively locked to prevent drift. Switch adjustments are
accessible when the cover is removed.
• AC Rating:
• 5 amps @125V
• 2.5 amps @240V
• DC Rating:
• (Inductive) 2.5 amps @30V
• (Resistive) 4.0 amps @30V
• Actuated by the 224 DPU
For flow applications, the unit is connected by tubing to
the LP and HP sides of the primary device (orifice plate,
venturi, or flow tube) in the process run. For liquid level,
the DPU is connected to measure the variations in DP
produced when the liquid level varies. These changes are
used to control the switch function.
The electrical alarm or control unit circuit is connected to
the switch (mounted on the DPU). Movement of the DPU
shaft actuates the switch mechanism when the DP reaches
a pre-set level.