Installation guide
Pressure switch
KPU
Application
KPU dual pressure switches are for use on commercial
refrigeration and air conditioning systems to protect
060R9768
compressor against excessively low suction pressure or
excessively high discharge pressure.
KPU dual pressure switches are compatible with refrigerants
listed below. KPU16W and KP16B are fail safe switches for high
pressure refrigerants. Standard enclosure is ~ NEMA 1.
Refrigerants:
R22, R134a, R404A, R407A, R407C, R407F, R410A*), R422B, R422D,
R438A, R448A, R449A, R450A, R452A, R507A, R513A
replace with:
For complete list of approved refrigerants, visit www.products.danfoss.
com and search for individual code numbers, where refrigerants are
listed as part of technical data. /
*) R410A only for KPU 16W and KPU 16B
KPU dual pressure switches are tted with the Single-Pole,
Single-Throw (SPST) or Single-Pole Double-Throw (SPDT)
switches, suitable for direct as well as indirect (with acontactor)
control.
Three versions of switch operation are available:
– automatic on LP and HP sides
– automatic on LP and manual reset on HP
– convertible manual or automatic on LP and HP sides.
Manual reset
The manual reset mechanism does not allow the pressure
switch to automatically reset after the switch has cut out. So the
pressure switch must be manually reset by the user to enable
restart of the equipment. Manual reset is possible to operate
only after return of pressure to cut in level. Before releasing
the reset it is recommended to investigate what caused the
shutdown.
Convertible reset
The convertible reset feature allows to change the operation
from automatic to manual by turning the selecting plate.
The selecting plate is located between two push buttons at the
top of the switch.
Please refer to instruction below demonstrating how to select
reset function.
060R9768
Product Specication
Code no. Low pressure (LP) High pressure (HP) Reset
Typ e
KPU 15 060 -5247 060 -5248 6 in – 108 10 – 60 100 – 465 60 Automatic Automatic
KPU 15B 060-52 49 060-525 0 6 in – 108 10 – 60 100 – 465 60 Automatic Man (Max.)
KPU 16W 060 -5251 060 -5252 6 in – 108 10 – 60 100 – 600 60 Automatic Automatic
KPU 16B 060 -5253 060-5254 6 in – 108 10 – 60 100 – 600 60 Convertible Convertible
Max. working pressure: LP side: 250 psig HP side KP U 15: 510 ps ig HP side KPU 16: 675 / 610* psig
Max. test pressure: LP side: 290 psig HP side KP U 15: 530 psig HP side KPU 16 : 725 psig
* 610psig - MWP for products used according to 2014/68/EU PED directive
1
⁄4 in
male are
36 in cap.
tube w. 1⁄4 in
are nut
Regulating
range
[inHg] [psig]
Dierential
Δp
[psi]
Regulating
range
[psig]
Dierential
Δp
[psi]
Low
pressure
High
pressure
Ambient temperature: -40 – 122 °F (175 °F for max. 2 hours)
Contact system
(NO + NC)
SPDT with
LP/HP signal
Convertible reset:
Selection of reset function on dual pressure switches with convertible
reset – turn plate to desired reset conguration.Insert a screwdriver into
the slot on the lock disc and turn it to desired reset conguration. Do not
turn the screw on the lock disc as it may damage the convertible reset
mechanism.
Danfoss
60-1408.11
SPST
LP man. LP auto. LP auto. LP man.
HP man. HP man. HP auto. HP auto.
© Danfoss | DCS (jmn) | 2017.01
Danfoss
DKRCC.PI.CD0.C6.02 | 520H11521 | 1
Installation
Select an accessible location, where the switch and pressure
connection line will not be subject to damage.
IMPORTANT:
Mount the pressure switch in a position that will allow
drainage of liquids away from switch bellows. Pressure
connection of the switch must always be located on the
top side of the refrigerant line. This reduces the possibility
of oil, liquids, or sediment collecting in the bellows, which
could cause theswitch malfunction.
IMPORTANT:
Ensure the ambient temperature for the dual pressure
switch on LP side is higher than the refrigeration line as
that will prevent liquid migration and accumulation in
the bellows.
For bracket mounting use only the 10-32x3/16 screws provided
with the switch. If other screws are used, function of the pressure
switch might be disturbed (they should not protrude into the
switch more than ⁄in).
Screws for
bracket mounting
Mounting holes
for at surfaces
Recommended
mounting position
Mount the KPU pressure switch on a bracket or on acompletely
at surface. Mounting to an uneven surface might cause
improper switch operation.
Recommendations for capillary tube and are connections:
1. Ensure self-draining of the capillary tube to minimize
clogging.
2. Coil excess capillary tube into smooth, circular coils (approx.
3 inch diameter). The coiled tube should be securely fastened
in order to prevent possible damage due to vibration.
3. Leave a little slack in the capillary tube as it helps to damp
mechanical vibrations.
4. Avoid sharp bends as well as re-bending of the capillary tube
on the same point as it weakens the material, increasing the
risk of crack.
5. Never allow for contact between the capillary tube and sharp
or abrasive objects as during vibrations the tube could be
damaged due to friction.
6. Purge the piping before connecting pressure switches.
7. Always use two wrenches
tightening the are nut on
the pressure switch. One
wrench should support the
connector while the second
wrench isused to tighten the
nut.
8. Do not over tighten are nuts as it may damage the threads
9. Protect the capillary tube from damage caused by vibrations
–
– when the switch is mounted remote from the compressor,
– when the switch is mounted remote from the compressor
Use only the mounting holes provided; no other holes
are to be added to the switch.
IMPORTANT:
Pressure pulsations in the refrigeration system reduce life
time of the bellows and might disturb switch function.
Pressure pulsations should always be eectively damped
e.g. by connection thepressure switches to the
refrigeration system through acapillarytube.
causing leaks.
from compressor:
when the switch unit is mounted directly on the compressor,
the capillary must be secured to the compressor so that
everything vibrates as a whole.
make the pressure connections away from thecompressor.
and the pressure connections have to be on the compressor,
then damping coils must be used between the compressor
and the pressure switch.
NOTE:
After installing the pressure switch, evacuate theplant in
accordance with applicable EPA and other regulations,
to remove air, moisture, and other contaminants.
2 | 520H11521 | DKRCC.PI.CD0.C6.02
© Danfoss | DCS (jmn) | 2017.01