PS1/PS2 Series Pressure Controls
Instruction Manual

Pressure Controls Series PS1 / PS2
OPERATING INSTRUCTIONS

General information:

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”.

Safety instructions:

• 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.) must 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!

Function:
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. 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.

Mounting location :
Any direction except upside down
Installation: (Fig. 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! 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

Pressure connection: (Fig. 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 counterbalance 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!

Pressure Test:
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.

Tightness Test:
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.

Electrical connection: (Fig. 4)

1. Range spindle
2. Lock plate
3. Differential spindle
4. Electrical terminals
5. Check-out lever
6. Cable entry grommet
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 considering 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.

Setpoint adjustment: (Fig. 5)

• PS1/PS2 pressure switches come with individually adjustable range and differential depending on the exact model.
• Manual reset switches always have a fixed differential.
• Use a flat screwdriver or a 1/4” refrigeration (square) wrench to adjust setpoints as described below.
• Adjust upper setpoint using the range spindle.
• Adjust lower setpoint by turning the differential spindle.

Upper setpoint – Differential = Lower setpoint

(1) Upper setpoint (2) Lower setpoint (3) Differential = constant (4) Turning range spindle

(5) Upper setpoint (6) Lower setpoint (7) Differential = variable (8) Turning differential spindle

• A separate gauge must be used for exact adjustment of the setpoints. The integrated display scale can only be used for obtaining approximate settings.
• When changing the upper setpoint the lower setpoint must be re-checked.
• Refer to the Emerson catalogue or Technical Information for standard factory settings.

Manual reset / Universal reset: (Fig. 6a-c)

• Manual reset (external): press the reset button (1) as indicated by Fig. 6a.
• Manual reset (internal): remove the housing cover and press the reset button (2) as indicated by Fig. 6b.
• Note that the reset is ‘trip-free’, i. e. reset is only possible if the pressure has reached its reset threshold.
• Universal reset: remove the cover and change the universal toggle to the desired position (manual (3) or auto reset (4).(Fig. 6c)

Check- out lever: ((5) Fig. 4 & Fig. 7)

• Use the check-out lever to manually override the electrical contact position for testing out the system.
• Use the check-out lever on low pressure switches to manually override the electrical contact position for evacuating the refrigeration system.

Service / Maintenance:

• Disconnect electrical power before service.
• In case of repair work or replacing the control always use a new gasket. (K-Types)
•  According to EN 378-4 during each periodic maintenance, tightness tests shall be carried out at the relevant part of the refrigerating system. This shall apply where appropriate following any repair.

Technical Data:

Medium compatibility	Fluid Group II  R448A, R449A, R513A, R450A, R134a, R452A, R23, R410A,  R407C, R404A, R507, R124, R1234ze (A2L)	Fluid Group R32, R452B, R454B, R454A, R454C, I R455A, R1234yf
Electrical rating	Resistive load (AC1)  24 A / 230 VAC Inductive load (AC15) 10 A / 230 VAC Inductive load (DC13) 0.1 A / 230 VDC 3 A / 24 VDC 6 A / 12 VDC Start-up (AC3)  144 A / 120 VAC / 230 VAC Motor rating (FLA) 24 A / 120 VAC / 240 VAC Locked rotor (LRA) 144 A / 120 VAC / 240 VAC	Resistive load (AC1)          10 A / 230 VAC* Inductive load (AC15)        1 A / 230 VAC*; 10 A / 24 VAC* Inductive load (DC13)        0.1 A / 230 VDC* 3 A / 24 VDC* 6 A / 12 VDC* Start-up (AC3)                  – Moto rating (FLA)             – Locked rotor (LRA)            – *) Acc. IEC 60335-2-40 max. electrical load = 2.5 kVA
NOTE: Use proper fuse for short circuit case by considering above voltages/currents
Protection class (IEC 529/EN 60529)	IP44
Temperature range TS |Storage / Transport / Ambient / Medium	-50 °C…+70 °C
Max. allowable pressure PS/ Test pressure PT	See Type code table
Vibration resistance (acc. EN 12263)	4 g (10…1000 Hz)
Standards	– EN 12263 – PED 2014/68/EU, Category IV for all devices with TÜV approval under EN12263	– LVD 2014/35/EU, – EN 60947-1, EN 60947-5-1
Marking	0035 for devices under PED              pending for devices under LVD            all types	all types (E85974) all types
Dimensions	See Fig. 2

Type Code:

Emerson Climate Technologies GmbH
Pascalstrasse 65 I 52076 Aachen I Germany
www.climate.emerson.com/en-gb

Documents / Resources

EMERSON PS1/PS2 Series Pressure Controls [pdf] Instruction Manual PS1, PS2, PS1 PS2 Series, Pressure Controls, PS1 Series Pressure Controls, PS2 Series Pressure Controls, Pressure Controls, PS2 Series, PS1 Series

References

• User Manual