Penn P77 Series User manual

P77 Series Controls for High Pressure and
Hazardous Location Applications Installation
Guide
Applications
P77 Series Controls for High Pressure and Hazardous
Location Applications provide high pressure control
using a low energy signal from inside an explosive
zone on commercial refrigeration and air-conditioning
applications. The controls have special dry circuit
switches with gold-plated contacts for improved contact
characteristics that are required in circuits with low
voltage and low current.
Important: Use this P77 Series Control only as an
operating control. Where failure or malfunction of
the control could lead to personal injury or property
damage to the controlled equipment or other
property, additional precautions must be designed
into the control system. Incorporate and maintain
other devices, such as supervisory or alarm systems
or safety or limit controls, intended to warn of or
protect against failure or malfunction of the control.
Important: Utiliser P77 Series Control uniquement
en tant que dispositif de contrôle de fonctionnement.
Lorsqu'une défaillance ou un dysfonctionnement
du contrôle risque de provoquer des blessures
ou d'endommager l'équipement contrôlé ou un
autre équipement, la conception du système de
contrôle doit intégrer des dispositifs de protection
supplémentaires. Veiller dans ce cas à intégrer de
façon permanente d'autres dispositifs, tels que
des systèmes de supervision ou d'alarme, ou des
dispositifs de sécurité ou de limitation, ayant une
fonction d'avertissement ou de protection en cas de
défaillance ou de dysfonctionnement du contrôle.
These controls are available in several pressure ranges
and are compatible with propane refrigerants. They are
designed to operate in:
• Group II, Zone 2 environments, as defined in the ATEX
Directive and UKEx regulations.
• Class I, Division 2, Group D environments, as defined
in NFPA 70 and CSA C22.2.
They are equipped with fail-safe double bellows and a
6 mm outer diameter copper tube. An adjustment lock
plate is included with these models.
IP54 (Type 1 NEMA) enclosures are standard on these
models.
P77 control models with Single-Pole, Double-Throw (SPDT)
switches allow users to install alarm devices or other
control circuits (see Figure 4).
Table 1 lists the features of P77 controls for high pressure
and hazardous location applications. This model is
available through most authorized Johnson Controls®/
Penn distributors.
Table 1: Standard P77 model for high pressure applications (for non-corrosive refrigerants)
Model number Pack type Switch action Range, barg
(psig)
Differential, bar
(psi)
Pressure
connection
Maximum
bellows
pressure, barg
(psig)
P77XAAW-18500C Individual pack SPDT (see Figure
4 and Table 2)
3 to 30
(50 to 435)
3.5 to 12
(44 to 174)
6 mm diameter
copper tube
33 (479)
Repair information
If the P77 Series Pressure Control fails to operate within
its specifications, replace the unit. For a replacement
P77 control, contact the nearest Johnson Controls/Penn
distributor or representative.
Installation
Important: Components within the P77 control can
exceed the enclosure temperature by 1°C (2.1°F).
For standard applications, limit the maximum media
temperature on the control to 80°C (176°F). When the
media temperature exceeds 80°C (176°F), you must
ensure that the media temperature does not cause a
thermal ignition risk on parts between the media and
the enclosure.
Part No. 24-7664-3221 Rev. C
2023-06-29
P77XAAW

Always install P77 series controls in refrigeration systems
that comply with European Ex installation standard, EN
60079-11, any local directive and legislation, and any other
regulation applicable.
Dimensions
See Figure 1 for control dimensions. These dimensions
are nominal and subject to accepted manufacturing
tolerances and application variables.
Figure 1: P77 High Pressure Control with IP54 (Type 1
NEMA) enclosure dimensions, mm (in.)
Mounting
NOTICE
Risk of Property Damage
Mount the P77 High Pressure Control according to the
instructions and guidelines included with the control.
These instructions and guidelines are intended to
reduce the risk of malfunction of the control and
resulting property damage. Failure to follow these
instructions and guidelines could cause the control to
malfunction, resulting in property damage.
AVIS
Risque de dégâts matériels
Montez le contrôle P77 selon les instructions et
directives fournies avec le contrôle. Ces instructions
et directives sont destinées à réduire les risques de
mauvais fonctionnement du contrôle et de dégâts
matériels. Le non-respect de ces instructions et
directives pourrait provoquer un dysfonctionnement
du contrôle et causer des dégâts matériels.
Important: When you mount the control to a flat
horizontal surface, use the screws provided and a
universal mounting bracket which is sold separately
to avoid damaging internal components. Be careful
not to distort or bend the control case when you
mount the control to an uneven surface. Using
other screws or bending the control case voids the
warranty.
Guidelines: Observe the following guidelines to mount
the P77 high pressure control:
• Mount the control in an accessible position, where the
control and pressure-connection lines are not subject
to damage.
• Mount the pressure control upright and level.
• Position the pressure-connection lines to allow
drainage away from the control bellows.
• Locate pressure-tap points on the topside of the
refrigerant lines to reduce the possibility of oil, liquids,
or sediment accumulating in the bellows, which could
cause control malfunction.
• Mount controls with IP54 (Type 1 NEMA) enclosures
on horizontal or vertical flat surfaces.
P77 Series Controls for High Pressure and Hazardous Location Applications Installation Guide2

Vertical Surface, see Figure 2: Use four M4 x 6 mm + d
screws (Callout 1) through the inner M4 holes (Callout 2)
on the back of the control case when mounting directly to
a flat vertical surface (Callout 3). Do not use screws longer
than 6 mm + d, where d refers to thickness of mounting
surface.
Figure 2: Mounting the P77 High Pressure Control on a
vertical surface
Callout Description
1 Four field supplied mounting screws for
vertical surface, M4 x 6 mm + d. Do not use
screws longer than 6 mm + d.
2 Four inner mounting M4 holes
3 Flat vertical mounting surface
Horizontal Surface, see Figure 3: Use four M4 x 6 mm
screws provided (Callout 1), and the universal mounting
bracket (Callout 3) which is sold separately, when you
mount the control to a flat horizontal surface.
Figure 3: Mounting the P77 High Pressure Control on a
horizontal surface
Callout Description
1 Four mounting screws for horizontal surface,
M4 x 6 mm (provided)
2 Four inner mounting M4 holes
3 Universal mounting bracket, Part Number
271-51 (1 pcs, NA only), 271-51L (50 pcs, EU
only), sold separately
Wiring
WARNING
Risk of Explosion or Fire
Do not disconnect the P77 Pressure Control while
its circuit is energized, unless the area is known to
be nonhazardous. Disconnecting the P77 Pressure
Control in a hazardous area while its electrical circuit
is energized may result in an explosion or fire, and
may cause serious injury or death.
AVERTISSEMENT
Risque de explosion ou incendie
Ne pas déconnecter le contrôle de pression P77
lorsque son circuit est sous tension, sauf s'il est avéré
que la zone est non dangereuse. La déconnexion du
contrôle de pression P77 dans une zone dangereuse
alors que son circuit électrique est sous tension
risque d'entraîner une explosion ou un incendie et de
provoquer des blessures graves, voire mortelles.
Important:
• Use copper conductors only. Make all wiring
connections in accordance with local, national,
and regional regulations. Do not exceed the
control’s electrical ratings.
• Use terminal screws furnished in the switch
block. Using other terminal screws voids the
warranty and may damage the switch.
• The P77 control must be wired through a reliable
means of limiting the voltage and current,
placed outside the hazardous zone, to ensure
insufficient energy supply to cause ignition of
the surrounding atmosphere by an electrical
spark or the heating of electrical components.
P77 controls for high pressure applications are available
with a Single-Pole, Double-Throw (SPDT) switch. Check
the label inside the control cover for the model number,
switch action, and electrical rating. Check the wiring
terminal designations on the control faceplate, and see
P77 Series Controls for High Pressure and Hazardous Location Applications Installation Guide 3

Figure 4 and Table 2 when wiring the control. Also see P77
technical specifications.
Figure 4: P77 switch wiring (SPDT)
Table 2: Single pressure control, low events, high
events, and model type
Switch and
action
Low event High event
SPDT A to B closes
on pressure
decrease.
A to C opens
simultaneously.
A to B opens
on pressure
increase.
A to C closes
simultaneously.
Use only cables and cable entries that are approved
for R290 (propane) applications. Do not allow cables to
come into contact with sharp edges. Install cables with
adequate stress relief to avoid pulling at the terminal.
Figure 5: Intrinsic safety protection method
Table 3: Entity parameters (P77 Pressure Control
parameters)
Parameter Maximum switch loads
Pi max (P max) 1 W
Ui Max (V max) 30 V
Ii Max (I max) 0.1 A
Ci max 0.5 nF
Li max 0.2 µH
The selected associated apparatus providing output entity
parameters must be third-party listed for the application,
and have intrinsically safe entity parameters that conform
with the guidelines outlined in the following table.
Table 4: Intrinsically safe entity parameters for the
associated apparatus
P77 Pressure Control Zener barrier or suitable
associated apparatus
Ui Max (V max) ≥ Voc or Vt (or Uo)
Ii Max (I max) ≥ Isc or It (or Io)
Pi max (P max) ≥ Po
Ci + Ccable ≤ Ca (or Co)
Li + Lcable ≤ La (or Lo)
Calculate the capacitance and inductance of the field
wiring from intrinsically safe equipment to the associated
apparatus and include them in the system calculations
as shown in Table 4. Cable capacitance, Ccable, plus
intrinsically safe equipment capacitance, Ci, must be
less than the marked capacitance, Ca (or Co), shown in
any associated apparatus used. The same applies for
inductance (Lcable, Li and La or Lo, respectively). If you
do not know the cable capacitance and inductance per
centimeter (foot), use the following values:
Ccable = 60 pF per 30 cm (1 ft), Lcable = 0.2 µH per 30 cm
(1 ft)
If you do not know the Po of the associated apparatus,
calculate it using the following formula:
Po = (Voc x Isc)/4 = (Uo x Io)/4
Install the associated apparatus in accordance with its
manufacturer’s control drawing and the ATEX Directive for
installation in Europe, Article 504 of the National Electrical
Code (ANSI/NFPA 70) for installation in the United States,
Section 18 of the Canadian Electrical Code for installation
in Canada, UKEx regulations in the UK, and all other
applicable codes. You can use the associated apparatus
in a Group II, Zone 2 or Class I, Division 2 location if the
apparatus is approved for the area.
Refrigerant connections
Important: If the control is installed on equipment
that contains hazardous or regulated materials
such as certain refrigerants or lubricants, you must
comply with all standards and regulations governing
the containment and handling of those materials.
P77 high pressure controls are connected to the
controlled equipment by a 6 mm diameter copper tube
solder connection to ensure a hermetic installation.
Avoid severe pressure pulsations at high pressure
connections. Install pressure connection to pressure-tap
points away from the compressor to minimize the effects
of pressure pulsations from reciprocating compressors.
Important: After you install the control, evacuate
the refrigerant pressure connection lines to remove
air, moisture, and other contaminants in a manner
consistent with applicable environmental regulations
and standards.
P77 Series Controls for High Pressure and Hazardous Location Applications Installation Guide4

Setup and adjustments
Important:
• Use the pressure control settings recommended
by the manufacturer of the controlled
equipment. Do not exceed the pressure
ratings of the controlled equipment or any
of its components when checking pressure
control operation or operating the controlled
equipment.
• After you install the control, attach a reliable
set of gauges to the controlled equipment, and
operate the equipment for at least three cycles
at the pressures necessary to verify control
setpoints and proper equipment operation.
• Do not adjust pointers beyond the highest or
lowest indicator marks on the control’s pressure
scale. Adjusting pointers beyond indicator
marks may damage screw threads, may cause
inaccurate control operation, and will void the
warranty.
Adjusting the P77 High Pressure Controls
Before you begin:
Find the model number and switch action on the product label inside the control cover. See Table 2 for switch action, low
event, high event, and model number. For high pressure cut-out with automatic reset, note that models with automatic
reset have a scaleplate that displays the cut-out and differential setpoints (Callout 1, Figure 6).
1. Set the cut-out setpoint (High Event; A opens to B) by adjusting the range screw (Callout 3).
2. Turn the range screw clockwise to raise the cut-out setpoint.
3. Set the cut-in setpoint (Low Event; A closes to B) by adjusting the differential screw (Callout 2).
4. Turn the differential screw clockwise to decrease the cut-in setpoint.
5. Apply the adjustment lock plate.
Note: Cut-in is equal to cut-out minus differential.
Figure 6: Adjusting P77 Controls for high pressure applications
Table 5: Adjusting P77 High Pressure Controls
Callout Description
1 Range and differential scales
2 Differential screw
3 Range screw
4 Adjustment lock plate
5 Pressure connection
P77 Series Controls for High Pressure and Hazardous Location Applications Installation Guide 5

P77 technical specifications
Table 6: P77 Series application technical specifications
Information Description
Product switch action Single-Pole, Double-Throw (SPDT)
Pressure connection 6 mm diameter copper tube
Ambient operating conditions Temperature: -20ºC ≤ Ta ≤ + 55ºC (-4ºF ≤ Ta ≤ 131ºF)
Humidity: 0 to 95% R.H. non-condensing
Enclosure Cast aluminum; IP54 (Type 1 NEMA)
Dimensions (H x W x D) Enclosure: 80 x 88 x 54 mm (3.15 x 3.5 x 2.13 in.)
Approximate shipping weight Individual pack: 0.5 kg (1.1 lbs)
Table 7: Conformity declaration information
Information Description
Purpose of control Pressure operating control: automatic reset controls
Construction of control Electromechanical
Number of cycles 30,000 cycles
Method of mounting control Independently-mounted control
Type 1 or Type 2 action Automatic: Type 1; Type 1.C (micro-interruption)
Pollution degree Category 1
Heat and fire resistance category N/A
Rated impulse voltage 330 V
Over-voltage Category 1
Ball pressure temperature 125°C (257°F)
Field wiring rating 0.5 mm2 to 1.5 mm2 (20 AWG to 14 AWG)
Maximum working pressure 30 barg (435 psig)
Cover screw torque requirements
instruction
Tighten enclosure screws to: 1.3 N·m to 1.6 N·m (12 in·lb to 14 in·lb)
Compliance
United States: UL Listed; UL 60730-1, File SA516. NFPA 70. Class I, Division 2.
Canada: cUL Listed; cUL E60730-1, File SA516. CSA C22.2. Class I, Division 2.
Europe: CE Mark — Johnson Controls declares that this product is in
compliance with the essential requirements and other relevant provisions of
the
Low Voltage Directive,
PED Directive: Category IV Safety Accessory,
ATEX: DEMKO 16 ATEX 1734,
Standards: EN 60079-0, EN 60079-11
United Kingdom: UKCA Mark — Johnson Controls declares that this product is
in compliance with the essential requirements and other relevant provisions of
the:
Electrical Equipment (Safety) Regulations 2016
Pressure Equipment (Safety) Regulations 2016: Category IV Safety Accessory
UKEx Regulations 2016: UL22UKEX2373
Standards: EN 60079-0, EN 60079-11
P77 Series Controls for High Pressure and Hazardous Location Applications Installation Guide6

The performance specifications are nominal and conform to acceptable industry standards. For application at conditions
beyond these specifications Johnson Controls shall not be liable for damages resulting from misapplication or misuse of
its products.
Product warranty
This product is covered by a limited warranty, details
of which can be found at www.johnsoncontrols.com/
buildingswarranty.
Software terms
Use of the software that is in (or constitutes)
this product, or access to the cloud, or hosted
services applicable to this product, if any, is
subject to applicable end-user license, open-source
software information, and other terms set forth at
www.johnsoncontrols.com/techterms. Your use of this
product constitutes an agreement to such terms.
Patents
Patents: https://jcipat.com
Single point of contact
APAC EU UK NA/SA
JOHNSON CONTROLS
C/O CONTROLS
PRODUCT MANAGEMENT
NO. 32 CHANGJIANG RD
NEW DISTRICT
WUXI JIANGSU PROVINCE
214028
CHINA
JOHNSON
CONTROLS
VOLTAWEG 20
6101 XK ECHT
THE NETHERLANDS
JOHNSON
CONTROLS
TYCO PARK
GRIMSHAW LANE
MANCHESTER
M40 2WL
UNITED KINGDOM
JOHNSON
CONTROLS
5757 N GREEN BAY
AVE.
GLENDALE, WI
53209
USA
Contact information
Contact your local Johnson Controls representative:
www.johnsoncontrols.com/locations
Contact Johnson Controls: www.johnsoncontrols.com/
contact-us
P77 Series Controls for High Pressure and Hazardous Location Applications Installation Guide 7

© 2023 Johnson Controls. All rights reserved. All specifications and other information shown were current as of document revision and
are subject to change without notice.
www.penncontrols.com