Grundfos PHT A N User manual

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GRUNDFOS INSTRUCTIONS
PHT A Pressurisation unit
Installation and Operating Instructions
Models: PHT A N/D/F/T/V
Residential and Commercial
ORIGINAL INSTRUCTIONS

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EC/EU Declaration of Conformity
Name of manufacturer: Grundfos Manufacturing Limited.
Address: Ferryboat Lane,
Castletown,
Sunderland.
SR5 3JL.
United Kingdom
We, Grundfos, declare under sole responsibility that the products PHT A-*, to which the
declaration below relates, are in conformity with the Council Directives listed below on the
approximation of the laws of the EC/EU member states.
•Machinery Directive (2006/42/EC).
Standards used: EN ISO 12100:2010
•Low Voltage Directive (2014/35/EU).
Standard used: EN 60335-1:2012 +A11:2014
•EMC Directive (2014/30/EU)
Standard used: EN 61000-6-1:2007 and EN 61000-6-3:2007+A1:2011
Standard used: EN 60730-1:2016
This EC/EU declaration of conformity is only valid when published as part of the Grundfos
Installation and Operating instructions (publication number 99354499).
Authorised signature:
John Austin –Engineering Manager
(Name) (Position)
Date of issue: 11/12/2017

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Table of Contents
1.0 About this manual.
2.0 Symbols used in this document.
3.0 Scope of these instructions.
4.0 Product identification.
5.0 Operating Principles.
5.1 Standard Pressurisation Unit.
5.2 Twin System Pressurisation Unit.
5.3 Glycol Pressurisation Unit.
6.0 General information.
6.1 Delivery and handling.
6.2 Delivery inspection upon receipt.
6.3 Warranty.
6.4 Site storage on receipt.
6.5 Weather, Temperature and long-term storage.
6.6 Operating Environment.
6.7 Installation Location.
6.8 General requirements.
6.9 Operating Conditions.
6.10 Wall Fixings.
6.11 Product weights.
7.0 System Controller Overview.
7.1 Programming the Controller.
7.2 Start-Up Sequence.
7.3 Main Operating Screen.
7.4 Menu Entry.
7.5 Menu System.
7.6 Function Tree
7.7 Fault Indication.
7.8 Fault Log.
7.9 Uploading the Fault Log.
7.10 Digital Outputs.
7.11 System 1 Interlock Output (D01).
7.12 General Fault Output (D02).
7.13 Programmable Outputs (D06/D07/D08).
8.0 Installation and commissioning –General.
8.1 PHT A-N/D/V unit –Float valve. adjustment
requirements.
8.2 PHT A-F/T unit –Float valve adjustment.
8.3 Priming the Pumps.
8.4 PTH-V Glycol settings.
8.5 Installation Checklist.
8.6 Commissioning Checklist.
8.7 Commissioning Record.
9.0 User Maintenance.
9.1 Planned Preventative Maintenance.
9.2 Annual Service.
10.0 Connection Drawing.
10.1 Wiring Diagram.
11.0 Spare parts list.
12.0 De-commissioning
12.1 De-commissioning.
12.2 Dismantling.
12.3 Disposal.
13.0 CIM Modules.
14.0 Fault finding checklist.
14.1 Fitting Procedure
15.0 Quick guides.
15.1 How to...Clear Excess Consumption Warning.
15.2 How to...Clear Flood Protection Fault.
15.3 How to…Program Digital outputs
15.4 How to…Upload the Fault log to USB memory
stick.
15.5 How to…Quickly check key system settings.
15.6 How to…Operate pumps in hand.
15.7 How to…Clear the Fault Log.
15.8 How to…Clear the Settings Log.
15.9 How to…Change the Pump FLC.
15.10 How to…Reset the Service Reminder.
16.0 History Log/Notes

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1.0About this manual.
This manual contains all the necessary information to install, commission, operate, maintain and
fault find on the Grundfos PHT A range of pressurization products. It is strongly recommended
that this manual should be fully read before undertaking any work on this equipment.
It is highly recommended that this equipment is commissioned by a Grundfos engineer.
Contact details for Grundfos Service can be found below.
Grundfos Pumps Ltd.,
Telephone: [phone]
** It is advisable that the Installation and Operating manual remains with
the product for the duration of the product lifecycle.
2.0 Symbols used in this document
WARNING(S)
If these safety instructions are not observed, it may result in personal injury or damage
to property.
If these instructions are not observed, it may lead to electric shock with consequent
risk of serious personal injury or death.
CAUTION
NOTE
If these safety instructions are not observed, it may result in malfunction or
damage to the equipment.
Notes or instructions that make the job easier and ensure safe operation.
3.0 Scope of these Instructions.
These Installation and Operating instructions apply to the:
Grundfos PHT A range of Pressurisation products
For all other Technical Information consult the PHT A Datasheet and sales brochure.
All the above documents can also be found on the Grundfos Product Center website at:
www.grundfos.co.uk
CAUTION
NOTE
NOTE
Static sensitive components, observe static sensitive handling procedures.
Product damage may occur

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4.0 Product Identification.
The PHT A unit has a silver label attached to the cabinet.
This label gives the following key information.
Fig. 1 –Product Nameplate
5.0 Operating Principles.
The function of the PHT A pressurization equipment is to continuously monitor the pressure within
hydronic pressurized heating and chilled water systems, maintaining the optimum operating
pressure by providing automatic pressurised water top when required to compensate for system
losses. (e.g. slow leaks, air venting, etc.).
The PHT A equipment will also provide signals and alarms for connection to building management
systems.
The PHT A equipment will not fill systems
The PHT A equipment will not cope with major water loss.
(e.g. System drain down, burst pipe)
The PHT A equipment is not intended to be used for water boosting applications
Please consult the appropriate datasheets for product selection
Three distinct types of unit are described in this document:
1. Standard Pressurisation Unit –Single and twin pump configurations
- Delivers water into a single system
2. Twin System Pressurisation Unit –Twin pump only
-Delivers water into two different systems
3. Glycol Pressurisation Unit - Twin pump only
-Delivers a mix of water and glycol into a single system
Part no.
Serial no.
Electrical data
Hydraulic data

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5.1 Standard Pressurisation Unit (PHT A-N/D/F models).
The following schematic shows the arrangement of the PHT A-N/D/F pressurisation models:
Fig. 2 –PHT A-N/D/F Schematic
The pressurisation unit is connected into the sealed system (System 1) through the System 1
Connection (6). The System 1 Isolation Valve (7) provides a point to isolate the unit from the
system. The System 1 Drain Valve (8) provides a point to drain down the unit and/or system and for
commissioning purposes.
The System 1 Pressure Transmitter (AI1) measures the pressure in System 1.
The PHT A unit can be configured with one or two pumps (P01 and P02) which when energised, will
transfer water from the Break Tank into System 1 to increase the pressure as required.
The pumps run in a duty/standby configuration where only one pump runs at a time (the duty
pump). The duty pump will always be the pump with the least accumulated total run time. This is a
measure to spread the wear evenly between the two pumps.
In single pump units Pump 1 (P01) permanently acts as the duty pump.
A Current Sensor (AI5) (not shown on schematic), measures the electrical current consumption of
Pump 1 (P01) and Pump 2 (P02) to detect faults in the pumps.
A System 1 Fault Output (DO1) (not shown on schematic) is used to interlock the boiler or chiller on
System 1 to disable it if the system pressure falls outside of safe operating limits. The fault name is
shown under the status bar on the Controller screen.
A General Fault Output (DO2) is provided to signal any fault presented by the unit.
Three additional outputs are provided which can be customised to signal a range of specific faults
or functions, Programmable Output 1 (DO6), Programmable Output 2 (DO7) and Programmable
Output 3 (D08).
The pressurisation unit is fitted
with a Break Tank (1) which is filled
from the Water Supply(2), via a
Float Valve(3). The break tank is
fitted with a Drain Overflow (4) in
case the Break Tank overfills, and a
Weir Overflow (5) in case the Drain
Overflow becomes blocked.
A Low Water Float Switch (DI1) is
fitted to detect a low water
condition.
A High Water Float Switch (DI2)
(optional extra) is fitted to detect
overfilling of the tank.

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5.2 Twin System Pressurisation Unit (PHT A-T models).
A variation of the design allows a single pressurisation unit to provide top-up for two systems,
referred to as a Twin System Pressurisation Unit.
The following schematic shows the arrangement of a twin system pressurisation unit:
Fig. 3 –PHT A-T Schematic
This design allows the pressurisation unit to provide top up to two systems independently, with
different parameters, using the same two pumps.
In addition to the features described for a standard pressurisation unit, the following additional
features are provided:
The pressurisation unit is connected into the second system (System 2) through the System 2
Connection (9) via the System 2 Isolation Valve (10), a manual valve provided for isolating the unit
from the system. The System 2 Drain Valve (11) is provided for draining down the unit and/or
system and for commissioning purposes.
The System 2 Pressure Transmitter(AI2) measures the pressure in System 2.
The System 1 Valve (DO3) directs flow from the pumps into System 1.
The System 2 Valve (DO4) directs flow from the pumps into System 2.
When used in twin system mode the Programmable Output 3 (DO8) is set to function as a
critical fault output for System 2 by default and cannot be changed.

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5.3 Glycol Pressurisation Unit (PHT A-V model).
Another variation of the design allows the unit to deliver a predetermined mix of water and glycol
into a single system.
The following schematic shows the arrangement of a glycol pressurisation unit:
Fig. 4 –PHT A-V Schematic
In addition to the features described for a standard pressurisation unit, the following additional
features are provided:
Glycol is held in the Glycol Tank (12). The Low Glycol Switch (DI3) detects when the glycol has run
out and requires refilling.
When the pumps run, they draw a predetermined mix of water and glycol out of the two break
tanks. The ratio of water to glycol is set by manually adjusting the Glycol Flow Regulator (13) with
respect to the Water Flow Regulator (14).

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6.0 General information.
6.1 Delivery and handling.
Except for the PHT ANunit all PHT A units are supplied from the factory
strapped to a wooden pallet suitable for handling by forklift equipment or similar.
The weight and size of the PHT A unit may require the use of proprietary lifting equipment to be
handled safely. Please observe the weight indicated on the packaging label before selecting
lifting method.
Do not stack items on top of the PHT A unit.
Do not drop the pallet/PHT A unit
6.2 Delivery inspection upon receipt.
The PHT A should be immediately unpacked and inspected.
Any damage must be reported to the supplier within seven days in writing or sooner.
It is important that this Installation and Operating manual is studied carefully before any
installation takes place. The installation and operation should also be in accordance with local
regulations and accepted codes of practice.
Under no circumstances should the unit be operated until correctly installed in the
system pipework and ensure that the controller cover and product cover are secured
in their appropriatepositions.
6.3 Warranty.
1. The Grundfos warranty covers all defects within the PHT A originating from faulty
workmanship and/or materials for a period of two years from the date of installation or
thirty months from the date of dispatch from the factory, whichever is the shorter.
2. The warranty covers the replacement of any faulty parts and our labour cost to replace the
faulty parts. It does not cover the cost of removing, returning and refitting the PHT A unit or any
secondary losses arising from the failure.
3. Under no circumstances should faulty equipment be dismantled.
Failure to comply with this instruction could invalidate the warranty.
4. Defects arising from incorrect installation, water containing debris, or harmful chemicals,
inadequate electrical protection, faulty ancillary equipment, lightning or other circumstances
beyond our control, are not covered by the warranty.
6.4 Site storage on receipt.
It is strongly recommended once the PHT A unit has been delivered to site, that it is placed
immediately into a dust, moisture and frost-free area which has been secured to prevent
unauthorised interference. If this is not possible then the unit should be stored in an area which
is as near as possible to the ideal storage conditions as described above.

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6.5 Weather, Temperature and long-term storage.
The PHT A unit needs to be protected against the weather and extremes of temperature during
summer and winter. Provision to maintain the PHT A’s operating conditions needs to be made
within the overall system design and location setting.
The PHT A unit must be protected from freezing conditions. Should the unit be placed outside
then the unit needs to be protected against the weather and consideration must be made for
trace heating and/or lagging.
The PHT A unit must be protected from heat. Should the unit be placed in an environment that
could potentially become hotter than the operational recommendations then air venting and
circulation must be considered.
If the PHT A unit is being stored during periods of frost the whole unit should be drained to
avoid damage. Remove all drain and vent plugs and allow the unit to drain.
Do not replace the plugs until the PHT A unit is to be used again.
6.6 Operating Environment.
The PHT A unit must not be used in an environment which has been classified as
hazardous where it could provide a source of ignition and therefore cause an explosion by
flame path.
Grundfos do not accept any responsibility for the use of the PHT A unit to pump liquids which
could be construed as being hazardous to health either by touch, ingestion or inhalation of
fumes or gases given off by the liquid.
6.7 Installation Location.
Careful consideration must be given to the location of the PHT A unit.
The following are minimum requirements:
The PHT A unit should ideally be placed in a location where the control panel and status LED can
readily be seen, and the internal buzzer heard withoutobstruction.
These are primary warning and alarm events and should be available to be observed and heard.
The pump must be vented/primed before it is started again.
Refer to the commissioning section.
Alternative system provision must be made for alerting the inhabitants to the
PHT A warnings and alarms if the control panel, status LED and buzzer cannot be
seen or heard.

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To enable maintenance and service of the PHT A unit to be carried out satisfactorily,
the area should have adequate lighting for this work to be carried outsafely.
Ensure that the PHT A is positioned to allow access for examination and service.
Allow the following:
A minimum of 50 cm above all units.
A minimum of 50 cm to the system connection side of all units.
A minimum of 100 cm to the front of the unit.
Adequate drainage facilities and protection from water damage in the immediate
vicinity of the PHT A unit must be provided.
If the PHT A unit is installed into a roof spaces, then provisions should be made for the
small level of vibration associated with any rotating equipment in case it causes
disturbance. Provision should also be made for drainage of the unit, leakage and any loss of water
during commissioning and service.
The PHT A unit should not be installed in an unventilated small space, ensure
adequate ventilation for the motor.
6.8 General requirements.
The installation pipework may need to be properly supported
before being connected to the PHT A unit so that the PHT A unit is not stressed.
The pipework installation to and from the PHT A unit should be in accordance with local
water authority regulations, best industry practice and according to any design
recommendation
The electrical installation of the PHT A unit should be in accordance with the latest issue
of the I.E.E. regulations and performed by a competent installer.
The equipment must be Earthed

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6.9 Operating Conditions.
Electrical supply: 230 V +10 /-6%, 50 Hz
Electrical load:
Model
Power (Watts)
Full Load current (Amps)
PHT A-N130/PHT A-N230
28 W
0.10 A
PHT A-D125/PHT A-D225
440 W
1.90 A
PHT A-D150/PHT A-D250
900 W
3.30 A
PHT A-F125/PHT A-F225
440 W
1.90 A
PHT A-F150/PHT A-F250
900 W
3.30 A
PHT A-F180/PHT A-F280
1150 W
6.0 A
PHT A-T225/PHT A-V225
440 W
1.90 A
PHT A-T250/PHT A-V250
900 W
3.30 A
Quiescent All models
15 W
0.07 A
Pollution Degree: 3 Noise level: <70 dB(A) at full speed
Liquid temperature range: +1°C to +60°C Ambient temperature: From +1°C to 40°C
Relative humidity: 95% (non-condensing)
Usage: Indoor (Outdoor, subject to restrictions found)
Type of protection: Class 1 (earthed) equipment
Equipment type: Stationary, fixed equipment
Construction type: Fixed construction, no moveable parts
EMC Environment: B (light industrial, commercial and residential)
Inlet pressure max: PHT A N/D/V Models: See Chapter 8.1 –Float Valve adjustment
All other PHT A Models: Low pressure seat 2.5 Bar (as fitted)
Medium pressure seat 6.0 Bar (option only)
6.10 Wall Fixings.
All units must be mounted/stood in the vertical position.
The PHT A-N and PHT A-D units are suitable for wall fixing.
The wall fixing dimensions are given below.
Fig 5. –Wall fixing dimensions
Refer to the Product weight table also.

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6.11 Product weights.
Part No.
Description
Gross Weight (Kg)
Net Weight (Kg)
99264904
PHT A N130
14
12
99264947
PHT A N230
15
13
99264948
PHT A D125
21
20
99264949
PHT A D150
22
21
99264951
PHT A D225
30
29
99264951
PHT A D250
31
30
99264963
PHT A F125
32
31
99264964
PHT A F150
33
32
99264965
PHT A F180
38
37
99264966
PHT A F225
39
38
99264967
PHT A F250
40
39
99264968
PHT A F280
47
46
99264977
PHT A V225
57
56
99264979
PHT A V250
58
57
99264969
PHT A T225
42
41
99264970
PHT A T250
43
42

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7.0 System Controller overview.
The front face of the PHT A controller has the following items.
Fig 6. - Controller front screen
The ON/OFF Switch is an illuminated switch indicating that the unit is powered ON/OFF.
The Display panel gives the Status of the unit, the current pressure, the Date and time when
operating without a fault. When operating with a fault the Status will indicate the fault detected.
The Display panel will auto-dim to save energy after a predefined period without operation.
The Keypad has:
•UP/DOWN keys used to move between pages and increase/decrease values.
•Home key to return to the Home page
•OK key to confirm a value entered/Access the password protected menu’s
•Return key to step back in the program
The Status LED gives a quick and easy Status for the unit.
Green –Status Healthy.
Red –Status Fault or Service/Fault.
The system status is also supported by an audible buzzer.
The buzzer activates with Critical faults and can be silenced by pressing and holding the OK key.
7.1 Programming the PHT A Controller.
The PHT A controller has a simple, intuitive and ergonomic design that is easy to pick up.
Fixed combination volt free outputs that allow critical and general fault monitoring.
Programmable outputs providing complete flexibility.
ON/OFF Switch
(Illuminated when ON)
Display panel
Keypad
Status LED
NOTE

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7.2 Start-Up Sequence.
Upon powering up the unit, the controller will display the PHT * and Grundfos for 3 seconds
followed by the software version for a further 3 seconds.
PHT *
Grundfos
14.25
7.3 Main Operating Screen.
When the unit is operating normally and the status is healthy the display will include:
Status: OK / System 1 Pressure and Value / Current Date and Current Time:
Status: OK
System 1 Pressure 1.5 Bar
23/08/2017
14.25
With the PHT A-T configuration, the display will also show System 2 Pressure and value:
Status: OK
System 1 Pressure 1.5 Bar
System 2 Pressure 2.0 Bar
23/08/2017
14.25
If a fault condition is active, then the Status will show FAULT and the line below will carry a
message indicating the fault. If more than one fault exists then the first detected fault is shown
until cleared, the next fault is then displayed.
Status: FAULT
Low Water
System 1 Pressure 1.5 Bar
23/08/2017
3/08/2017
Software Version
V*.*
To interrogate all existing fault
conditions press the DOWN key and
scroll through the active faults.
See section 7.7 for more details.
NOTE

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Status: FAULT
Sensor
System 1 Pressure Bar
23/08/2017
14.25
Status: SERVICE
System 1 Pressure 1.5 Bar
23/08/2017
14.25
Status: FAULT - SERVICE
Sensor
System 1 Pressure Bar
23/08/2017
14.25
Settings Summary
High Alarm 1.5 Bar
Set Press 1.5 Bar
Diff Press 0.2 Bar
Low Alarm 0.7 Bar
Common Diff ON
If a pressure sensor fault has been
registered, then no pressure reading will
be shown:
If the unit requires servicing, then the
Status will show SERVICE:
If a fault is present and a service is
required, then the Status will show
FAULT - SERVICE:
To check the main settings quickly all in
one place press the UP key.
With the PHT A T unit there are two
screens of settings available.
NOTE

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7.4 Menu Entry.
To enter the password protected menus press and hold down the OK key for three seconds
The screen will prompt for a 4-digit numeric password:
Enter Password
_ _ _ _
Use the UP/DOWN keys to get to the required number before pressing the OK key to confirm.
When the OK key is pressed the cursor moves onto the next character.
7.5 Menu System.
The menu system opens at the first page in navigate mode.
The arrow at the bottom of the screen indicates that there are further pages.
01
Current Time:
14:25
To enter the edit mode and edit the value press the OK key, the cursor will appear, use the
UP/DOWN keys to change the value. Confirm the new value by pressing OK key.
If the value has two or more fields then the cursor will automatically move to the next field.
If the page has an arrow at the top, this indicates that there are preceding pages.
Once the value of the last field has been confirmed the menu system will return to the navigation
mode. Repeat these operations for all parameters requiring change.
The final screens in the menu allow for the manual operation of the pump(s) via pressing and
holding the OK key. This will activate the pump(s) while the key is held down and is only active in
the Engineering menu.
Any changed parameters will not come into effect until the Menu system has been exited.
To exit the menu system, press the HOME key.
If no keys are pressed for 5 minutes, then the system will automatically return to the Main
Operating screen. If there are any pending edits (values changed but not confirmed) then the
change will be discarded.
Not all parameters are available for Edit in the User menu.
Please see the table below.
User Password: 4321
Parameter
Value
Page number
NOTE

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Function Tree
User Access (4321)
Eng Access
7.6 Function Tree.
Page Parameter
1 Current Time
2 CurrentDate
3 Service Reminder
4 No. of Pumps
5 PumpAnti-seize
6 Pump Anti-seizePeriod
7 Pump FLC
8 Pump Over CurrentThreshold
9 Pump Under CurrentThreshold
10 Pump Trip delay
11 Pressure Alarmdelay
12 Low Water ResetTime
13 System 1 SetPressure
14 System 1 DifferentialPressure
15 CommonDifferential
16 System 1 Low Pressure AlarmON
17 System 1 Low Pressure AlarmOFF
18 System 1 High Pressure AlarmON
19 System 1 High Pressure Alarm OFF
20 System 1 Pump Hold OFFTime
21 System 1 Pump Run ONTime
22 System 1 FloodProtection
23 System 1 ExcessiveConsumption
24 System 2 SetPressure
25 System 2 DifferentialPressure
26 System 2 Low Pressure AlarmON
27 System 2 Low Pressure AlarmOFF
28 System 2 High Pressure AlarmON
29 System 2 High Pressure Alarm OFF
30 System 2 Pump Hold OFF Time
31 System 2 Pump Run ONTime
32 System 2 FloodProtection
33 System 2 ExcessiveConsumption
34 Pump 1 Total Run Time (Resetable)
35 Pump 2 Total Run Time (Resetable)
36 Pump 1 Starts (Resetable)
37 Pump 2 Starts (Resetable)
38 Pump 1 Last RunDate
39 Pump 2 Last Run Date
40 System 1 Pump Runtime PastHour
41 System 2 Pump Runtime PastHour
42 System 1 Pump Starts Past Month(Resetable)
43 System 2 Pump Starts Past Month(Resetable)
44 SoftwareVersion
45 Fault Log (View and Clear History)
46 Last Service date (Resetable)
47 Programmable Output1
48 Programmable Output2
49 Programmable Output3
50 Pump 1 Test (Press and Hold)
51 Pump 2 Test (Press and Hold)
52 Valve Test (Open/Close)

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7.7 Fault Indication.
The presence of an active fault condition will be shown on the operating screen:
Status: FAULT
Sensor
System 1 Pressure Bar
23/08/2017
14.25
Pressing the Down key will take the operator straight into the list of current faults.
The fault number is displayed, along with the name of the fault, relevant value (if applicable),
date and time. The presence of the arrow indicates further fault pages.
The operator can scroll through the list of faults, acknowledging them with the OK key.
Once a fault has been acknowledged it will disappear from the list.
Once all faults have been acknowledged (or a timeout period of 3 minutes has elapsed) then
the controller will return to the Main Operating screen. If the fault is cleared but still
detected as present then the fault message and status return, with a new date and time
stamp.
7.8 Fault Log.
The Fault log will store a minimum of 30 historic fault conditions in non-volatile memory.
This includes faults that have been acknowledged via the operating screen.
Access to the list of stored faults is through the Engineers menu.
The Fault log can be cleared down at any time after pressing the OK key and following the
instructions on the screen.
01
SENSOR
23/08/2017 14:25
02
HIGH PRESSURE 2.9 Bar
14/07/2017 11:30

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7.9 Uploading the Fault Log.
The Fault log can be uploaded to a standard size USB memory stick as a text file at any time
while the PHT A unit is switched ON by simply inserting the memory stick into the USB port
found on the reverse of the display unit and waiting approximately ten seconds before
removing it. Along with the Fault log the text file written to the memory stick will include
Current settings and Change history. The text file is date and time stamped for reference.
Examples:
Current Settings Change History Fault History
Set Pressure:1.5 Bar Setting change 1 of 2 Fault 41 of 43
Differential Pressure:0.2 Bar Service Reminder: ON Fault Type - System1 Low Pressure
Common Differential YES Date - 21/02/2019 Date - 09/06/2017
Pressure Alarm ON:0.7 Bar Time - 17:14 Time - 08:13
7.10 Digital Outputs.
All of the digital outputs can be hard wired as Normally Closed (NC) or Normally Open (NO).
The terminals are identified on the PCB, Connection and Wiring Diagrams
The digital outputs are volt free contacts (VFC’s)and rated for up to:
5A @ 30 VDC or 10A @ 250 VAC
7.11System 1 Interlock Output(DO1) is activated by any of the following alarms:
•System 1 Low Pressure
•System 1 High Pressure
•System 1 Sensor Fault
•Mains Power failure
These are the conditions under which the boiler or chiller on System 1 should be disabled.
The fault buzzer will cycle between ON for 5 seconds and OFF for 10 seconds continuously until
muted by pressing and holding the OK key for 2 seconds.
7.12General Fault Output(DO2) is activated by any of the following alarms:
•Pump 1/2 Over Current
•Pump 1/2 Under Current
•Low Water/High Water (only when fitted)
•Low Glycol (only on V model)
•System 1/2 Flood Protection (only on T model)
•System 1/2 Excessive Consumption (only on T model)
•System 1/2 Low Pressure (only on T model)
•System 1/2 High Pressure (only on T model)
•System 1/2 Sensor Fault (only on T model)