Spirax Sarco BC3150 User manual

BC3150
Blowdown Controller
Installation and Maintenance Instructions
1. Safety information
2. User instructions and
delivery information
3. System overview
4. Mechanical installation
5. Electrical installation
6. Commissioning
- Quick set-up
- Full
7. Communications
8. Maintenance
9. Fault nding
10. Technical information
- Default settings
11. Appendix
- Data registers
12. Menu map
IM-P403-88
AB Issue 5
4033352 /5
BC3150
x1000
x100
x10
OK
AL
CLN
IM-P402-88 AB Issue 5
IM-P402-130 AB Issue 7
Commissioning password
Current legislation states that in order to prevent tampering and potentially
hazardous programming errors, access to the pass codes required to enter
commissioning mode should only be available to qualified and trained
personnel.
Enter commissioning
To enter the commissioning mode, press and hold the OK button for 5 seconds.
The display will show the pass code '888'. Enter the pass code '745'. This is fixed
and cannot be changed.
If the wrong passcode is entered, the display will return to showing the current
process variable - run mode.
Special features
CALIBRATION from the Run Menu
Enables the operator (e.g. water treatment engineer / specialist) to calibrate the
controller from the run menu. A pass code is not required.
-Using the button, select 'CAL'.
-Pressing
OK
button will access the calibration menu in commission mode. See
Section 6.3.10 CAL- calibration.
-On completion or exiting calibration, the display will return to the process
variable run menu and normal control will be resumed.
This page MUST be removed after
commissioning
and kept in a safe,
access controlled location.
Printed in the UK © Copyright 2013
Printed in GB

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IM-P402-88 AB Issue 5

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1. Safety information
Safe operation of this product can only be guaranteed if it is properly installed,
commissioned, used and maintained by qualified personnel (see Section 1.11) in
compliance with the operating instructions. General installation and safety instructions
for pipeline and plant construction, as well as the proper use of tools and safety
equipment must also be complied with.
Your attention is drawn to IEE Regulations (BS 7671, EN 12953, EN 12952 and EN 50156).
Elsewhere, other regulations will normally apply.
All wiring materials and methods shall comply with relevant EN and IEC standards
where applicable.
Warning
This product is designed and constructed to withstand the forces encountered during
normal use. Use of the product other than as a boiler controller, or failure to install the
product in accordance with these Instructions, product modifications or repair could:
-Cause injury or fatality to personnel.
-Cause damage to the product / property.
-Invalidate the marking.
These instructions must be stored in a safe place near the installation of the product
at all times.
Warning
This product complies with Electromagnetic Compatibility Directive 2004 / 108 / EC
and all its requirements.
This product is suitable for Class A Environments (e.g. industrial). A fully detailed EMC
assessment has been made and has the reference number UK Supply BH BC3150 2008.
The product may be exposed to interference above the limits of Heavy Industrial
Immunity if:
- The product or its wiring is located near a radio transmitter.
- Excessive electrical noise occurs on the mains supply. Power line protectors (ac)
should be installed if mains supply noise is likely. Protectors can combine filtering,
suppression, surge and spike arrestors.
- Cellular telephones and mobile radios may cause interference if used within
approximately 1 metre (39") of the product or its wiring. The actual separation
distance necessary will vary according to the surroundings of the installation and
the power of the transmitter.
This product complies with Low Voltage Directive 2006 / 95 / EC by meeting the
standards of:
- EN 61010-1:2010 Safety requirements for electrical equipment for measurement,
control, and laboratory use.
Static precautions (ESD)
Static precautions must be observed at all times to avoid damage to the product.

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Symbols
Equipment protected throughout by double insulation or reinforced
insulation.
Functional earth (ground) terminal, to enable the product to function
correctly.
Not used to provide electrical safety.
Clean earth / ground.
Safety earth.
Caution, risk of electric shock.
Caution, risk of danger, refer to accompanying documentation.
Optically isolated current source or sink.
Caution, Electrostatic Discharge (ESD) sensitive circuit. Do not touch
or handle without proper electrostatic discharge precautions.
ac, alternating current.

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1.1 Intended use
i) Check that the product is suitable for use with the intended fluid.
ii) Check material suitability, pressure and temperature and their maximum and
minimum values. If the maximum operating limits of the product are lower than
those of the system in which it is being fitted, or if malfunction of the product could
result in a dangerous overpressure or overtemperature occurrence, ensure a
safety device is included in the system to prevent such over-limit situations.
iii) Determine the correct installation situation and direction of fluid flow.
iv) Spirax Sarco products are not intended to withstand external stresses that may be
induced by any system to which they are fitted. It is the responsibility of the installer
to consider these stresses and take adequate precautions to minimise them.
v) Remove protection covers from all connections and protective film from all
name-plates, where appropriate, before installation on steam or other high
temperature applications.
1.2 Access
Ensure safe access and if necessary a safe working platform (suitably guarded)
before attempting to work on the product. Arrange suitable lifting gear if required.
1.3 Lighting
Ensure adequate lighting, particularly where detailed or intricate work is required.
1.4 Hazardous liquids or gases in the pipeline
Consider what is in the pipeline or what may have been in the pipeline at some
previous time. Consider: flammable materials, substances hazardous to health,
extremes of temperature.
1.5 Hazardous environment around the product
Consider: explosion risk areas, lack of oxygen (e.g. tanks, pits), dangerous gases,
extremes of temperature, hot surfaces, fire hazard (e.g. during welding), excessive
noise, moving machinery.
1.6 The system
Consider the effect on the complete system of the work proposed. Will any proposed
action (e.g. closing isolation valves, electrical isolation) put any other part of the
system or any personnel at risk?
Dangers might include isolation of vents or protective devices or the rendering
ineffective of controls or alarms. Ensure isolation valves are turned on and off in a
gradual way to avoid system shocks.
1.7 Pressure systems
Ensure that any pressure is isolated and safely vented to atmospheric pressure.
Consider double isolation (double block and bleed) and the locking or labeling of
closed valves. Do not assume that the system has depressurised even when the
pressure gauge indicates zero.
1.8 Temperature
Allow time for temperature to normalise after isolation to avoid danger of burns.

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1.9 Tools and consumables
Before starting work ensure that you have suitable tools and /or consumables
available. Use only genuine Spirax Sarco replacement parts.
1.10 Protective clothing
Consider whether you and / or others in the vicinity require any protective clothing
to protect against the hazards of, for example, chemicals, high / low temperature,
radiation, noise, falling objects, and dangers to eyes and face.
1.11 Permits to work
All work must be carried out or be supervised by a suitably competent person.
Installation and operating personnel should be trained in the correct use of the
product according to the Installation and Maintenance Instructions.
Where a formal 'permit to work'system is in force it must be complied with. Where
there is no such system, it is recommended that a responsible person should know
what work is going on and, where necessary, arrange to have an assistant whose
primary responsibility is safety. Post ‘warning notices'if necessary.
1.12 Handling
Manual handling of large and/or heavy products may present a risk of injury. Lifting,
pushing, pulling, carrying or supporting a load by bodily force can cause injury
particularly to the back. You are advised to assess the risks taking into account the
task, the individual, the load and the working environment and use the appropriate
handling method depending on the circumstances of the work being done.
1.13 Residual hazards
In normal use the external surface of the product may be very hot.
Many products are not self-draining. Take due care when dismantling or removing
the product from an installation.
1.14 Freezing
Provision must be made to protect products that are not self-draining against
frost damage in environments where they may be exposed to temperatures below
freezing point.
1.15 Disposal
On disposal of the unit or component, appropriate precautions should be taken in
accordance with Local / National regulations.
Unless otherwise stated in the Installation and Maintenance Instructions this
product is recyclable and no ecological hazard is anticipated with its disposal
providing due care is taken.
1.16 Returning products
Customers and stockists are reminded that under EC Health, Safety and Environment
Law, when returning products to Spirax Sarco they must provide information on any
hazards and the precautions to be taken due to contamination residues or mechanical
damage which may present a health, safety or environmental risk. This information
must be provided in writing including Health and Safety data sheets relating to any
substances identified as hazardous or potentially hazardous.

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2. User instructions and
delivery information
Certain computer programs contained in this product were developed by Spirax-Sarco
Limited ("the Work(s)").
Copyright © Spirax-Sarco Limited 2013
All rights reserved
Spirax-Sarco Limited grants the legal user of this product (or device) the right to use the
Work(s) solely within the scope of the legitimate operation of the product (or device).
No other right is granted under this licence. In particular and without prejudice to the
generality of the foregoing, the Work(s) may not be used, sold, licensed, transferred,
copied or reproduced in whole or in part or in any manner or form other than as expressly
granted here without the prior written consent of Spirax-Sarco Limited.
Test the
alarm
2.1 General description
The BC3150 is a blowdown controller
for steam boilers. It controls TDS (total
dissolved solids – salts in solution) by
opening and closing a blowdown valve.
The product works by controlling the
conductivity of liquids, in conjunction with
a Spirax Sarco conductivity sensor, a boiler
blowdown valve or condensate dump valve.
2.2 Front panel
The front panel has a 3 digit LCD graphic
display and a five-button keypad:
Manually open valve
Scroll up the menu
Start probe
clean function
Fig. 1 Keypad and front panel definitions
2.3 Using the buttons
- Press the button to scroll through the menus.
- The OK button is used to enter the commissioning mode (press and hold for five seconds).
- The AL button can be used to test the alarm relay and the external circuits.
LCD
display
OK
BC3150
x1000
x100
x10
OK
AL
CLN
Clears errors
(Press and hold for 5 seconds)
Button
If pressed when CAL is selected, the
product can be calibrated from the run
menu, without having to access the
password protected commissioning
menu.

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2.4 Manual test buttons (in priority order)
Note: When these buttons are released, the product will return to 'PV' or 'end' depending if
pressed in run or commissioning mode.
AL Alarm button
This button can be used to test the alarm relay and the external circuits. The product will display,
'AL' + 'tSt' (meaning test) + 'PV' (TDS of conductivity) Note: The Alarm only occurs whilst the
key is pressed.
Valve button
This button can open the valve. If a purge time is set, the valve will remain open for the preset
purge time and will update the TDS reading. The product will display 'PV' + 'Pur' (meaning
purge) + 'bLd' (meaning blowdown). The purge interval will be reset. If continuous mode is
selected (purge time = 0) the valve will open for a minute. The product will display 'PV' + 'bld'.
Note: In commission mode, the valve only opens whilst the key is pressed.
CLN
Manual clean button
This button can electrically clean the probe for 20 seconds. The product will display PV + CLn
(meaning clean). On completion of the cleaning time, the controller will revert to normal control
after another 20 seconds. This is to allow any bubbles to disperse. Note: In commission mode,
the cleaning only occurs whilst the key is pressed.
Additional information on probe cleaning
If it is found that the calibration has drifted to more than twice its original setting, then the probe
may need cleaning.
15 minutes after the probe has been cleaned, it should then be possible to recalibrate the
controller near to its original level. If not, the probe may not be sufficiently clean, so repeat
the cleaning procedure. In most cases the controller can then be recalibrated. In exceptional
circumstances, where abnormal scaling has been allowed to occur in the boiler, it may still not
be possible to recalibrate the controller. In this case, it is permissible to repeat the cleaning
period in 5-minute steps up to a maximum of 30 minutes, checking the calibration after each
step. Wait for 15 minutes after each cycle to allow the system to stabilize.
Important note: The use of the probe cleaning function must not be regarded as a substitute
for adequate water treatment. If scale is forming on the probe tip it is a certain warning that
scale will also be forming on the boiler tubes. Boiler water treatment must be investigated.
Over-use of the probe cleaning function may shorten the life of the probe.
2.5 View parameter mode
Press the button in run mode to view and step through the parameters selected. Each
parameter will remain on view for a further 2 minutes unless the button is pressed again.

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2.6 LCD display
After initially applying power to the product, it will automatically enter run mode. The current
conductivity or TDS will then be displayed or 000 if a purge time has been set or the product
has not been calibrated.
In normal operation (run mode) the display shows the actual Total Dissolved Solids (TDS)
value in µS/cm or ppm, depending on the option chosen.
All ranges and operating parameters are selected using the software menu.
Once fully commissioned, the TDS value will alternate with information about alarms and the
valve status.
Example of alarm status:
If a blowdown occurs, 'bLd' will be displayed, followed by the type of blowdown.
Example of valve status:
Actual TDS value

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Probe cleaning / conditioning
The operator has started a cleaning cycle.
2.7 Information line details (in priority order):
Alarm:
The operator is testing the alarm relay.
The PV value has exceeded the alarm level.
Indicates the alarm relay has been de-energised/released.
TDS blowdown valve (Total Dissolved Solids):
The TDS is has increased above the Set Point (SP), and the blowdown valve is
being pulsed open for 10 seconds on, and 20 seconds off, until the TDS drops
below the hysteresis of the SP.
Indicates the blowdown relay is energised.
The TDS has increased above the Set Point (SP), and the blowdown valve has
been opened until the TDS drops below the hysteresis of the SP.
Is displayed if a during a purge period (valve open). At the end of this time the
product will either indicated 'Hi' or restart another purge interval.
The operator is testing the blowdown valve.
2.8 Alarm /error display messages
If an error occurs, an error menu 'ErX' will be displayed at the end of the parameter screens.
Pressing and holding the OK button for 3 seconds can clear a message and re-energize the
alarm relay(s). If the cause has not been corrected, the same error message will reappear. If
the error or alarm is of a latching type, only the message will disappear. The alarm relay will
remain de-energised until the correct passcode is entered in the commissioning menu. If more
than one error or alarm has occurred, the next message will appear (in priority order) after the
previous one has been cleared. See Section 9 - Fault finding.

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2.9 Equipment delivery, handling and storage
Factory shipment
The product is tested, calibrated and inspected prior to shipment to ensure proper operation.
Receipt of shipment
Each carton should be inspected at the time of delivery for possible external damage. Any visible
damage should be recorded immediately on the carrier’s copy of the delivery slip.
Each carton should be unpacked carefully and its contents checked for damage. If it is found that
some items have been damaged or are missing, notify Spirax Sarco immediately and provide
full details. In addition, damage must be reported to the carrier with a request for their on-site
inspection of the damaged item and its shipping carton.
Storage
If the product is to be stored for a period prior to installation, the environmental storage conditions
should be at a temperature between 0°C and 65°C (32°F and 149°F), and between 10% and
90% relative humidity (non-condensing).
Ensure there is no condensation within the unit before installing and connecting the power.
Operators instructions
An alternative operator instruction manual, in place of this manual, for operating the equipment
is required. This will avoid the commissioning menu passcode being disclosed to the operator.
The alarm reset passcode may optionally be disclosed if this is deemed necessary.

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3.1 Function
The product can be configured to control TDS / conductivity of water.
Once fully commissioned, the TDS value is displayed in μS/cm (or ppm if selected).
Note: Conductivity is expressed in parts per million (ppm) or micro Siemens per centimetre
(µS/cm). Micro Siemens /centimetre is becoming the more common unit, and is therefore
the default setting.
If the water conductivity exceeds the Set Point level, the TDS value shown on the display will
alternate with ‘bLd', and the valve relay will be energised until the conductivity drops below 5%
of full scale (FS) below the set point.
If the system is carrying out a purge, The TDS value will alternate with 'Pur', and the valve
relay will be energised until the conductivity drops 5% (FS) below the Set Point.
If the water conductivity exceeds the alarm level, the displayed TDS value will alternate
with 'AL', and the valve relay will be energised until the conductivity drops 3% (FS) below
the alarm level.
3.2 Inputs
The product can accept a signal from a Spirax Sarco conductivity probe (CP10 or CP30)
and a Pt100 temperature sensor. A CP32 probe may also be used with the BC3150, but will
not provide the scale monitoring and self-cleaning features.
A Pt100 temperature sensor may be connected to provide temperature compensation (2%/°C).
This is recommended if the boiler is working at varying pressures, or for other applications,
such as condensate monitoring or coil boilers, where the temperature may vary. If a Pt100 is
not fitted, the product uses a default temperature of 184°C (10 bar g).
3.3 Outputs
3.3.1 Continuous output
Used when the probe is mounted in the boiler. The probe is able to constantly monitor the
conductivity from the probe tip to the boiler shell.
3. System overview
Fig. 2 Continuous output (purge time = 0s)
Water
conductivity
SP
Hysteresis
Valve
open
Closed
High conductivity
Time
Blowdown
Keeps valve open until
conductivity drops below
hysteresis

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3.3.2 Purge output
Used only when the probe is mounted in the blowdown line, Purge ensures the sensor measures
the conductivity at boiler temperature. The purge duration time is the time the valve is open to
enable a representative boiler sample to reach the probe. A purge occurs every 30 minutes
either independent of burner firing, or dependent on cumulative boiler firing time.
3.3.3 Pulsed output
For smaller boilers where the capacity of the blowdown valve is relatively high compared to
the boiler size, the blowdown may be set to pulsed, rather than continuous output, opening
for 10 seconds, and closing for 20 seconds. This slows the rate at which the boiler water is
removed so that the level is not unduly affected, avoiding the risk of triggering a low water alarm.
3.3.4 4 - 20mA retransmit
An isolated 4 - 20 mA output is provided as standard, and may be used for remote display
of the TDS level or as an output to a computerised management system.
3.4 Other features
To prevent unwanted or inadvertent changes being made, most commissioning parameters
are protected with a pass code.
The BC3150 can communicate via an infrared link between adjacent controllers – see
Section 7, Communications.
Fig. 3 Output with purge time set (>0s)
Low valve
open
Valve
closed
Interval
10s
Purge Blowdown Blowdown Blowdown
Conductivity drops
below set point
Blowdown cycle
20s 20s
Purge Blowdown
Time
Fig. 4 Pulse output with purge time set (>0s)
Water
conductivity
SP
Hysteresis
Closed
High conductivity
Time
Purge Purge
Interval
Blowdown
Keeps valve open until
conductivity drops below
hysteresis
Valve
open
Water
conductivity
SP
Hysteresis

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BC3150
x1000
x100
x10
OK
AL
CLN
BC3150
x1000
x100
x10
OK
AL
CLN
Fig. 5 BCS1 system
Fig. 6 BCS2 system
3.5 Typical applications - Boiler control systems (BCS)

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BC3150
x1000
x100
x10
OK
AL
CLN
Fig. 7 BCS3 system
BC3150
x1000
x100
x10
OK
AL
CLN
Fig. 8 BCS4 system

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3.6 Typical applications -
condensate contamination detection system (CCD)
System description
Note: Most countries have regulations that limit temperature and contamination levels for
fluids being dumped to drain. It is also essential to follow guidelines issued by bodies such
as the UK Health and Safety Executive.
The Spirax Sarco CCD system monitors and displays the conductivity of condensate return,
and will redirect the flow to drain if the conductivity increases above a pre-set level to avoid
contaminated water being returned to the boiler feedtank. It will not detect contaminants that
do not change the conductivity, such as oils, fats, or sugars.
A conductivity sensor and a temperature sensor are mounted in a bypass line as
shown in Figure 9. A check valve in the main line ensures a flow past the sensor under
low flow conditions. The 500 mm head prevents flash steam flow in the bypass line.
We recommend a 3-port diverter valve such as the Spirax Sarco QL. A spring retract
pneumatic actuator is normally fitted to cause the valve to divert on failure of the air supply.
Alternatively, two 2-port valves (M20, for example) may be used as shown in Figure 10,
one as a spring-to-close isolating valve in the condensate return line, and one as
a spring-to-open dump valve, in the drain line. On detection of high conductivity, the
isolating valve closes and the dump valve opens, both under spring pressure.
Suitable 3-port solenoid valves may be selected from the Spirax Sarco range, and are
described in separate literature.

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Fig. 9 Typical application - CCD system
OK
BC3150
100
50
0
%
SP PV AL
Dump valve (spring-to-open).
Opens when conductivity level
is above set point allowing
contaminated condensate to
flow to drain.
Isolating valve (spring-to-close) opens to allow
clean condensate to be returned to the boiler.
Fig. 10 Alternative arrangement of a CCD system using separate valves
Spring retract
pneumatic actuator
QL
3-port diverter valve
Check valve
Bypass line
Conductivity sensor
and
temperature sensor
500 mm
head

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4. Mechanical installation
Note: Read the 'Safety information'in Section 1 before installing the product.
The product must be installed in a suitable industrial control panel or fireproof enclosure
to provide impact and environmental protection. A minimum of IP54 (EN 60529) is
required. If installed in a harsh environment (conductive dust and / or wet conditions),
extra protection is required.
During installation or maintenance, the rear of the product must be protected from
environmental pollutants entering the product. Alternatively, the tasks can be performed
in a dry clean environment.
Caution 1: The product must only be installed in the vertical orientation.
Caution 2: Do not cover or obstruct the infrared beam between products.
Ensure that the display can be easily read by the operator.
Warning: The boiler control panel or enclosure doors must be kept closed at all
times unless installation or maintenance work is being carried out.
4.1 Environmental conditions
Install the product in an environment that minimises the effects of heat, vibration, shock and
electrical interference (see Section 1 -Safety information).
Do not install the product outdoors without additional weather protection.
Do not attempt to open the product -it is sealed and has no replaceable parts or
internal switches.
4.2 Installation on a DIN rail
The product is provided with a clip and a set of self-tapping screws to secure it to a 35 mm DIN
rail. On the rear of the enclosure, two sets of holes are provided to give two height positions.
The clip can be adjusted to give further positions. Locate the clip onto one set of holes and
secure it using the two screws provided. Ensure the spring clip is fully engaged with the rail.
Warning: Only use the screws provided with the product.
4.3 Installation on a chassis plate:
- Drill holes in chassis plate as shown in Figure 11.
- Fit unit to chassis plate and secure with 2 screws, nuts and washers, using the slots
provided at the top and bottom of the case.
Warning: Do not drill the product case or use self-tapping screws.
4.4 Installation in a panel cutout:
(Minimum panel thickness 1 mm if the bezel is used).
- The product has integral threaded inserts (M4 x 0.7) at the top and bottom of the front
panel.
- Two M4 x 25 mm screws are provided, together with fibre washers and a bezel.
Warning:
Do not use screws over 25 mm in length -danger of electric shock.

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Fig. 11 Chassis plate / panel -cutout diagram
Fixing template cutout notes:
- Solid line indicates cutout required for panel mounting.
- Broken line indicates product outline.
- A minimum gap of 15 mm between units must be provided for product cooling.
- Mounting hole dimensions are the same for both panel and wall mounting.
112 mm
67 mm
10 mm
45 mm
92 mm
22 mm
22.5 mm
Ø 4.2 mm
Ø 4.2 mm
15 mm
Ø 4.2 mm
Ø 4.2 mm
10 mm
- Cut the panel to the dimensions given in Figure 11. Drill the screw holes in the panel in
the positions indicated.
- Remove the backing from the gasket supplied and apply to front face of the product.
- The bezel can be used to enhance the appearance of the panel cutout. If required, fit this
to the outside of the panel.
- Fit the unit from the rear of the panel, and secure using the screws, washers (and bezel)
provided.
- Tighten the M4 screws to 1.0 - 1.2 Nm.
Warning: Do not drill the product case or use self-tapping screws.

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5. Electrical installation
Note: Before installing read the 'Safety Information'in Section 1.
Warning:
Isolate the mains supply before touching any of the wiring terminals as
these may be wired to hazardous voltages.
Use only the connectors supplied with the product, or spares obtained from
Spirax Sarco Limited. Use of different connectors may compromise product
safety and approvals. Ensure there is no condensation within the unit before
installing and connecting the power.
Connecting the mains supply incorrectly can cause damage and may
compromise safety.
5.1 General wiring notes:
Every effort has been made during the design of the product to ensure the safety of the
user but the following precautions must be observed:
1. Maintenance personnel must be suitably qualified to work with equipment having
hazardous live voltages.
2. Ensure correct installation. Safety may be compromised if the installation of the product
is not carried out as specified in this IMI.
3. The design of the product relies on the building installation for overcurrent protection
and primary isolation.
4. Overcurrent protection devices rated at 3 amp must be included in all phase conductors
of the installation wiring. If overcurrent protection is included in both supply wires then the
operation of one must also cause the operation of the other. Refer to IEC 60364 (Electrical
Installations of Buildings) or National or local standards for full details of requirements
for overcurrent protection.
5. A 1 A quick-blow overcurrent protection device must be fitted to the burner input if used.
6. A 3 A quick-blow overcurrent protection device must be fitted to the relay circuit(s).
7. Relay contacts must be supplied on the same phase as the mains supply.
8. The product is designed as an installation category III product.
9. Install wiring in accordance with:
- IEC 60364 - Low-voltage electrical installations.
- EN 50156 Electrical Equipment for furnaces and ancillary equipment.
-BS 6739 - Instrumentation in Process Control Systems: Installation design and practice
or local equivalent.
10. It is important that the cable screens are connected as shown in order to comply with
the electromagnetic compatibility requirements.
11. All external circuits must meet and maintain the requirements of double/ reinforced
installation as stated in IEC 60364 or equivalent.