Hansen HA4A series User Manual

REGULATOR VARIATIONS
HA4A STANDARD REGULATOR
This most common pressure regulator
modulates to control evaporator
pressure, condensing pressure,
pressure in a vessel, or pressure in a
portion of a system. It is frequently
called an evaporator pressure regulator
(EPR) or back pressure regulator. Opens
on rising inlet pressure. See page 10.
Shown with M3W pilot.
HA4AS REGULATOR WITH
ELECTRIC SHUT-OFF
This control is commonly used for
temperature control or defrost.
Regulates at the set-for pressure when
energized. When de-energized, the valve
closes tight regardless of the pressure
setting. See page 11.
HA4AB REGULATOR WITH
ELECTRIC WIDE OPENING
Commonly regulates for defrost or
temperature, but opens wide for
maximum cooling. Regulating at the set-
for pressure when de-energized;
regulator opens when energized. See
page 11.
HA4AD DUAL PRESSURE
REGULATOR
Regulates (evaporator) pressure at a
setting when energized, and at a higher
setting for defrost, temperature control,
or pressure relief when de-energized.
See page 11.
HA4AL DIFFERENTIAL
PRESSURE REGULATOR
Commonly used as liquid pump relief,
condenser-receiver pressure difference
control, discharge pressure boosting for
defrosting or heat recovery, and other
similar applications. This control
modulates to maintain the set-for
difference between inlet and outlet
pressure. See page 10.
HA4AK RESEATING
RELIEF REGULATOR
Used for defrost, high-to- low side relief,
or nonatmosphere relief to other parts of
the system. This control opens when
system upstream pressure is above the
tagged and sealed set point pressure,
and repeatedly reseats after operation.
See page 10.
HA4A
HA4AS
HA4AB
HA4AD
HA4AL
HA4AK
HA4AO OUTLET
PRESSURE REGULATOR
Controls outlet pressure by opening
as downstream pressure falls below
the set point. Used for hot gas to
provide artificial refrigeration loading,
for condenser and receiver pressure
control by means of gas bypass,
limiting hot gas pressure supply in
defrosting evaporator in conjunction
with liquid drain traps, or
for HA4AO
compressor suction pressure limitation.
Can be combined with electric shut-off,
temperature-operated, dual, or wide-
opening features. See page 11.
HA4AP PNEUMATICALLY
COMPENSATED REGULATOR
Commonly used for precise air or liquid
temperature
control
via pneumatic
controller. An air, vapor, or liquid
pressure signal to the control module
bonnet increases inlet pressure from
HA4AP
the set-for pressure value at a 1:1 ratio.
See page 12.
HA4AT TEMPERATURE
OPERATED REGULATOR
The vapor pressure capillary tubing
and bulb system modulates the
regulator open
as
temperature
increases to control air or liquid
temperature. See page 12.
HA4AT
HA4AJ ELECTRONICALLY
CONTROLLED REGULATOR
Electronic pilot and controller provides
very precise temperature control of
various cooled media under fluctuating
load conditions. See page 12.
HA4AJ
HA4AM ELECTRIC MOTOR
COMPENSATED REGULATOR
Commonly used for precise room
temperature control or liquid chiller
control. The controlling motor changes
regulator
pressure
setting
in
accordance
with
a
temperature
controller. See page 13.
HA4AM
NOTE: Many other control functions can be achieved
by combining the control modules in different
arrangements. For example: a dual regulator with
electronic pilot and secondary relief pilot; i.e. HA4ADJ.
3
R429d
MAR 2002

Hansen HA4A series Specifications

General

Brand	Hansen
Model	HA4A series
Category	Controller
Language	English