Pressure Controls Series PS1 / PS2
For application in refrigeration systems and heat
pumps.
!
Safety instructions:
• Read
installation
instructions
Failure to comply can result in device failure,
system damage or personal injury.
• It is intended for use by persons having the
appropriate knowledge and skill.
• Before opening any system make sure pressure
in system is brought to and remains at
atmospheric pressure.
• Ensure supply voltage and current of electric
device match rating on PS1/PS2 name plate.
Disconnect supply voltage from system and
PS1/PS2 before installation or service.
• Do not exceed test pressure.
• Keep temperatures within nominal limits.
Function / Type of switch (Fig. 1, 4):
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. Reaching the preset switch point on rising
pressure, contact 1-2 opens while contact 1-4 closes
and vice versa on falling pressure.
Fig. 1b: 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.
• PS1/PS2 with manual reset are "trip-free".
Mounting (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!
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
Mounting direction:
Any direction except upside down
Pressure connection (Fig. 3):
• Connection of the pressure side depends on the
exact model / pressure connector.
• Connectors A, C, F and S: Do not apply torsional
load to pressure connnector; use second spanner to
counter-balance torque when tightening pressure
connection.
• Connector A: high pressure versions (pressure
range '5') are equipped with a snubber to dampen
pulsations.
• 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.
• K-type connectors: use copper gasket supplied with
control.
PS12_65048.doc / 05
Operating Instructions
Leakage test:
After completion of installation, a test pressure must
be carried out as follows:
- According to EN378 for systems which must
comply with European pressure equipment directive
thoroughly.
97/23/EC
- To maximum working pressure of system for other
applications
Warning:
- Failure to do so could result in loss of refrigerant
and personal injury.
- The pressure test must be conducted by skilled
persons with due respect regarding the danger related
to pressure.
Maintenance/Service:
In case of repair work or replacing the control always
use new gasket.
Electrical connection (Fig. 4):
(1) Range spindle
(2) Lockplate
(3) Differential spindle
Note: Comply with local electrical regulations when
conducting electrical wiring. Wire size must match
the electrical load connected to the switch contacts.
• 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 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):
(1) Upper setpoint
(2) Lower setpoint
(3) Differential = constant
(4) Turning range spindle
• 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 screw driver or a ¼" refrigeration
(square) wrench to adjust setpoints as described
below.
• Adjust upper setpoint using the range spindle.
• Adjust lower setpoint by turning the 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 ALCO catalogue for standard factory
settings.
Manual reset / Universal reset (Fig.6):
• 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
treshold.
• Universal reset: remove the cover and change the
universal toggle to the desired position (manual (3)
or auto reset (4) ).
Check-out lever (5) (Fig. 4)
• 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.
replaces / ersetzt PS12_65048.doc / 04
Heerstr.111 – D-71332 Waiblingen
GB
(4) Electrical terminals
(5) Check-out lever
(6) Cable entry grommet
(5) Upper setpoint
(6) Lower setpoint
(7) Differential = variable
(8) Turning differential spindle
Upper setpoint – Differential =
Lower setpoint
PCN 0715180
Emerson Electric GmbH & Co. OHG
Tel.: 07151 509-0 - Fax.: -200
www.ecopeland.com/alcoliterature.cfm
Standards
• EN 12263: specific models
• Pressure Equipment Directive PED 97/23/EC,
Category IV for all devices with TÜV approval
under EN12263
• Low
Voltage
93/68/EWG; EN 60947-1; EN 60947-5-1
• UL/CSA: all models
•
0035 marking for devices under PED
•
marking for devices under LVD
Technical data:
• Protection class:
• Ambient temperature (housing):
• Storage / transportation temperature: -50°C ..+70°C
• Medium/allowable temperature TS: -50°C .. +70°C
• Test pressure PT: see fig. 7
• Max. allowable pressure PS: see fig. 7
• Vibration resistance:
• Electrical rating
Heating load (AC1):
Inductive load (AC15):
Inductive load (DC13):
• Start-up (AC3):
Motor rating (FLA):
Locked rotor (LRA):
• Medium compatibility:
not released for inflammable refrigerants
Type code:
PS1 – (1) (2) (3) PS2 – (1) (2) (3) e.g. PS1-A 5 A
(1) Function
A = Pressure control, automatic
B = Pressure cut out, external manual reset,
TÜV/EN12263 approval,
C = (PS2) Left: pressure limiter, automatic,
TÜV/EN12263. Right: pressure cut out,
external manual reset, TÜV/EN12263
G = (PS2) Left: pressure cut out, external man reset,
TÜV/EN12263. Right: safety pressure cut out,
internal manual reset, TÜV/EN12263
L = (PS2) Left: automatic pressure control.
Right: pressure control, extern. manual reset
M = (PS2) Left: automatic pressure control.
Right: convertible reset from R to A
R = Pressure control, external manual reset
S = Safety pressure cut out, internal manual reset,
TÜV/EN12263 approval
T = (PS2) Left: pressure limiter, automatic, TÜV/
EN 12263. Right: safety pressure cut out,
internal manual reset, TÜV/EN12263.
U = Convertible from function 'R' to 'A'
W = Pressure limiter, automatic,
TÜV/ EN12263 approval
NOTE: Function types B, R or S in combination
with pressure range 1, 2 or 3 have a low pressure
manual reset function and latch with falling
pressure. Function types B, R, S in combination with
Pressure Range 4 or 5 have a high pressure manual
reset function and latch with rising pressure
(2) Pressure range (Fig. 7)
(PS: max. allowable pressure / PT: test pressure)
(3) Pressure connection (Fig. 3)
7
A =
/
"-20 UNF, male
16
1
C = R
/
" male, stainless steel with steel bellows
4
K = cap. tube, nut
opener
1
R = R
/
" male, brass
4
L = ¼"-ODM solder with 1 m cap tube
U = 6 mm ODF solder, 80 mm length
X = ¼"-18 NPTF, steel (incl. bellows)
1 / 7
Directive
LVD
73/23/EWG;
IP44 (IEC 529/EN 60529)
-50°C .. +70°C
4g (10...1000 Hz)
24A / 230V AC
10A / 230V AC
0.1A / 230V DC
3A / 24V DC
144A / 230V AC
24A / 230V AC
144A / 230V AC
HFC, HCFC
7
/
"-20UNF, schrader valve
16
20.07.2005