Emerson Alco Controls PS1 Series Operating Instructions Manual

G e n e r a l i n f o r m a t i o n :
For application in refrigeration systems and heat pumps.
The device has a potential ignition source and has not
been qualified according to ATEX standards. Installation
only in "non-explosive location".
S a f e t y i n s t r u c t i o n s :
• Read operating instructions thoroughly. Failure to
comply can result in device failure, system damage or
personal injury.
• This product is intended for use by qualified personnel
having the appropriate knowledge and skills like trained
according to EN 13313 or a specific training for
flammable refrigerants.
• Flammable refrigerants require special handling and
care due to its flammability. Sufficient ventilation is
required during service of the system.
• Contact with rapidly expanding gases can cause
frostbite and eye damage. Proper protective equipment
(gloves, eye protection, etc.) has to be used.
• Ensure that the system is correctly labeled with applied
refrigerant type and a warning for explosion risk.
• In a severely contaminated system, avoid breathing acid
vapors and avoid contact with skin from contaminated
refrigerant / lubricants. Failure to do so could result in
injury.
• Before opening any system make sure pressure in
system is brought to and remains at atmospheric
pressure.
• Do not release any refrigerant into the atmosphere!
• Do not exceed the specified maximum ratings for
pressure, temperature, voltage and current.
• Ensure that the system piping is grounded.
• Before installation or service disconnect all voltages
from system and device.
• Observe and avoid mechanical damage of housing in
order to maintain protection class.
• Do not use any other fluid media without prior approval
of EMERSON. Use of fluids not listed could result in:
- Change of hazard category of product and
consequently change of conformity assessment
requirement for product in accordance with European
Pressure Equipment Directive 2014/68/EU.
• Ensure that design, installation and operation comply
with European and national standards/regulations.
• For flammable refrigerants only use valves and
accessories approved for it!
F u n c t i o n
Fig. 1a: automatic reset function:
• PS1/PS2 Pressure switches are equipped with SPDT
snap action contacts switching from 1-2 to 1-4 on rising
and from 1-4 to 1-2 on falling pressure.
Fig. 1a
Fig. b: manual reset function for low pressure reset /
Fig. 1c: manual reset function for high pressure reset:
• PS1/PS2 with manual reset (high pressure/low pressure
reset): Reaching the preset switching point contact 1-4
switches to 1-2 (low pressure switch) or from 1-2 to 1-4
(high pressure switch) and locks in this position. After the
pressure rises or drops by a fixed differential the switch
can be reset by pushing the reset button.
Fig. 1b
Fig. 1c
Emerson Climate Technologies GmbH
Pascalstrasse 65 I 52076 Aachen I Germany
O P E R A T I N G I N ST RU C T I O N S
Pressure Controls Series PS1 / PS2
M o u n t i n g l o c a t i o n :
Any direction except upside down
I n s t a l l a t i o n : ( F i g . 2 )
• PS1/PS2 controls may be installed by using a mounting
plate or as a wall-mounted device against a flat surface.
• Use universal thread M4 or UNC8-32 mounting holes for
installation via mounting plate.
• Use the standard mounting holes at the backside for wall
mounting.
• Use mounting screws supplied with control.
• Mounting screws must not penetrate control backside by
more than 8 mm to ensure proper operation.
• Do not use PS1/PS2 in pulsating operating conditions!
In order to achieve protection class IP44, the following
instructions must be observed:
• Cover must be closed and cover screw fastened
• Control must be mounted against a flat surface so that all
openings on the housing backside are fully covered
P r e s s u r e c o n n e c t i o n : ( F i g . 3 )
• Connection of the pressure side depends on the exact
model / pressure connector.
• When connecting PS1/PS2 to the hot gas line of a
refrigeration system, a pipe, capillary or flexible tube of at
least 80 mm shall be used to allow sufficient temperature
drop between refrigeration line and pressure switch
bellows.
Threaded connection:
• Connectors A & C: Do not apply torsional load to
pressure connector; use second spanner to counter-
balance torque when tightening pressure connection.
• K-type connectors: use copper gasket supplied with control.
Brazing connection:
• Perform the brazing joint as per EN 14324.
• Before and after brazing clean tubing and brazing joints.
• Minimize vibrations in the piping lines by appropriate
solutions.
• Do not exceed the max. surface temperature of 70 °C!
P r e s s u r e T e s t :
After completion of installation, a pressure test must be
carried out as follows:
- according to EN 378 for systems which must comply with
European pressure equipment directive 2014/68/EU.
- to maximum working pressure of system for other
applications.
T i g h t n e s s T e s t :
Conduct a tightness test according to EN 378-2 with
appropriate equipment and method to identify leakages
from joints and products. The allowable leakage rate must
be according system manufacturer's specification.
Warning:
• Failure to pressure test or tightness test as
described could result in loss of refrigerant, damage
to property and/or personal injury.
• The tests must be conducted by skilled personnel
with due respect regarding the danger related to
pressure.
E l e c t r i c a l c o n n e c t i o n : ( F i g . 4 )
(1) Range spindle
(2) Lockplate
(3) Differential spindle
(7) Pressure Connection
• Entire electrical connections have to comply with local
regulations.
• Wire size must match the electrical load connected to
the switch contacts.
• Ensure that the cables are mounted without tension;
always leave the cable a bit loose.
• Ensure that cables are not mounted near sharp edges.
• Do not bend or mechanically stress the cable outlet,
maintain a clearance of 20 mm to neighboring parts .
• Feed cables through rubber grommet at switch bottom.
• Optionally, the rubber grommet may be replaced by a
standard PG 13.5 cable gland.
• Connect wires to terminals by taking into account switch
functions as shown in Fig. 1a to Fig. 1c.
• Fasten terminal screws with torque 1.2 Nm max.
• For electronic applications with low electrical loads
(voltage < 24 V and current <50 mA) gold plated contacts
are recommended.
www.climate.emerson.com/en-gb
S e t p o i n t a d j u s t m e n t : ( F i g . 5 )
• PS1/PS2 pressure switches come with individually
• Manual reset switches always have a fixed differential.
• Use a flat screw driver or a 1/4" refrigeration (square)
• Adjust upper setpoint using the range spindle.
• Adjust lower setpoint by turning the differential spindle.
Fig. 5
(1) Upper setpoint
(2) Lower setpoint
(3) Differential = constant
(4) Turning range spindle
• A separate gauge must be used for exact adjustment of
• When changing the upper setpoint the lower setpoint
• Refer to the Emerson catalogue or Technical Information
M a n u a l r e s e t / U n i v e r s a l r e s e t : (Fig. 6a-c)
• Manual reset (external): press the reset button (1) as
• Manual reset (internal): remove the housing cover and press
• Note that the reset is 'trip-free', i.e. reset is only possible
• Universal reset: remove the cover and change the
C h e c k - o u t l e v e r : ( ( 5 ) F i g . 4 & F i g . 7 )
• Use the check-out lever to manually override the
• Use the check-out lever on low pressure switches to
S e r v i c e / M a i n t e n a n c e :
• Disconnect electrical power before service.
• In case of repair work or replacing the control always use
• According
(4) Electrical terminals
(5) Check-out lever
(6) Cable entry grommet
OI_PS1(2)_A1_A2L_EN_DE_FR_ES_IT_RU_Rev11_0715180.docx
adjustable range and differential depending on the exact
model.
wrench to adjust setpoints as described below.
Upper setpoint – Differential = Lower setpoint
(5) Upper setpoint
(6) Lower setpoint
(7) Differential = variable
(8) Turning differential
spindle
the setpoints. The integrated display scale can only be
used for obtaining approximate settings.
must be re-checked.
for standard factory settings.
indicated by Fig. 6a.
the reset button (2) as indicated by Fig. 6b.
if the pressure has reached its reset threshold.
universal toggle to the desired position (manual (3) or
auto reset (4).(Fig. 6c)
electrical contact position for testing out the system.
manually override the electrical contact position for
evacuating the refrigeration system.
a new gasket. (K-Types)
to EN 378-4 during
maintenance, tightness tests shall be carried out at the
relevant part of the refrigerating system. This shall apply
where appropriate following any repair.
EN
each periodic
Date: 30.03.2022