Galvanic Isolator Gi-120/BK User manual

Note:
Suitable for shore supplies supplied by
an RCD (Earth Leakage Circuit
Breaker) with a trip current not
exceeding 30mA, and an MCB (Circuit
breaker) not exceeding 16A.
Ensure that no ground connections on
the vessel bypass the Galvanic isolator.
If in doubt, please consult a qualified
electrician, or call us. We will be glad to
Advise.
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Tel: [phone] www.galvanic-isolator.co.uk
Galvanic Isolator
Gi-120/A Gi-120/BK
Instructions
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IMPORTANT:
To prevent water ingress, before
installation, and
periodically, check
Gland Nuts on both
ends for tightness (Blue
in photo). They should
be as tight as possible
USING HAND FORCE
ONLY.
Model Gi-120/A >>
<< Model Gi-120/BK
Tel: [phone] www.galvanic-isolator.co.uk

G
Galvanic Isolator
i
The galvanic isolator protects your
boat from corrosion caused by
galvanic and leakage currents that
arise due to chemical inter- actions between your
boat and nearby boats/structures and bank- side.
The Galvanic Isolator simply connects to EITHER end of your shore line. It can be connected either
at the boat end or the shore end. Both options work equally well.
Locate your isolator where it will not be subjected to excessive heat,
physical damage or water ingress, particularly the plug & socket.
(Rain is acceptable - immersed or in running water is not).
When installed, to avoid water ingress, we strongly advise that the
cable entries to the isolator the connectors should point downwards.
Gi-120/A Gi-120/BK
Installation - Fixing the Isolator
Locate a suitable position for the isolator, ideally protected from excess heat,
moisture etc.
The cable entries must point downward. Although the isolator is protected against
water, it is still wise to keep it, and the connectors as dry as possible.
The Isolator may be mounted to practically any flat surface.
The most secure method of mounting is to use the screw positions inside the isolator enclosure.
Alternatively, it can be fixed using either a mastic type adhesive, or a double sided adhesive tape
available from all DIY stores. If mounting using adhesive, please ensure that surfaces are sound,
clean and dry. Support the isolator until adhesive has fully set, and use cable clips to prevent undue
stress on the adhesive.
If using screws, remove the isolator lid, taking care not to stretch the
internal wiring. The lid may be disconnected for ease of access. To
disconnect, pull the CONNECTORS apart. Do NOT pull the cables!
Carefully drill the screw positions in each corner of the enclosure. Drill
JUST large enough to accept the mounting screws you will use.
Mark the screw positions on the surface to which the isolator is to be
mounted, and pilot drill or drill & tap holes as neccessary.
Fix with chosen screws, taking care not to overtighten, as this could
damage the enclosure.
To prevent water ingress, apply a small amount of sealant on the rear of
the isolator at the screw positions, and fix the isolator to the surface.
Continued...
Fixing Points
Circled Red

Installation - Fixing the Isolator continued
As a further measure to prevent water ingress, when fixed, apply a little sealant to the heads of the fixing
screws.
If the lid has been disconnected, re-connect the terminals, ensuring that
they are pushed fully home.
Re-fix the isolator lid. The screws should be tightened firmly, taking care
not to overtighten.
Note:
Isolators may be supplied with the connectors either way around. If you wish to
change them this is permissible. Simply interchange the connectors, paying
attention to polarity. Please ensure connecting screws and gland nuts are tight.
To open the connectors, please press clip (see photo), and twist connector
body halves in opposite directions.
If in doubt, please seek advice from a qualified person.
IMPORTANT:
To prevent water ingress, before installation, and
periodically, check Gland
Nuts on both cable ends for
tightness (Blue in photo).
Gland Nuts should be as tight
as possible USING HAND
FORCE ONLY.
Installation - Connecting the Isolator
Switch off the electricity supply at the shore supply, and disconnect
the shore line.
Connect the isolator to the chosen end of the shore line.
Connect the free end of the isolator to the boat or shore connector.
Switch on the electricity supply at the shore supply.
Check that the RCD test button on the boat operates normally
You are now protected.

Both Lights OFF: Normal operation. No
action required – just check back
occasionally to ensure that all’s well.
One Light ON: If either light is on, DC leakage
is indicated. This can cause severe corrosion
to your boat. Following pages give clear basic
advice on how to resolve the problem.
Both Lights ON: If both lights are ON, this
indicates AC leakage, usually from the mains
wiring or a connected appliance. AC leakage
can be a danger to life. Please see
instructions for help in rectifying the problem.
The LED's on your isolator inform you about any faults with your boats
Earthing arrangement. Illuminated LED's NEVER indicate a faulty isolator.
Model Gi-120/BK only

Occasionally, when you fit a Status Monitored galvanic isolator, both of the
warning lights may glow straight away.
If both lights are illuminated on your galvanic isolator, you have AC earth
leakage. You do NOT have a faulty isolator. In fact, your isolator is alerting
you to a potentially dangerous situation that you may not previously have
been aware of.
There are two main types of earth leakage: Mains Leakage and Imprinted Leakage.
Mains Leakage
Mains Leakage happens when an appliance, cable or connection has poor
insulation resistance, and some of the circuit’s current “leaks” away to earth. If there
is sufficient leakage, the earth leakage circuit breaker, also known as the RCD, will
trip, disconnecting the supply.
At lower levels of leakage, although the RCD may not trip, the lights on your
galvanic isolator may still glow, alerting you to the likelihood of earth leakage.
Usually, an earth leakage fault will only get worse, so you should always take this
seriously and investigate.
No two electrical systems are the same, so it’s only possible to give the broadest
suggestions of how to locate any problem. Usually some detective work is required,
and this starts by switching off the main RCD on the boat. In most cases, this will
result in the lights on the isolator going out. If not, there is probably something
connected to the mains supply BEFORE the RCD.
Ensure that the electrical supply is disconnected
before working on a circuit, and remember that in
some systems, an auxiliary supply such as an inverter
may automatically kick in when the mains supply is
disconnected. If you are in any doubt, you should
entrust the work to a competent person.
!
Assuming the lights go out when the RCD is switched off, switch off ALL the circuit bbreakers, then switch the RCD back on. In most cases, the isolator’s
lights will stay off. You can then switch the circuit breakers back on one at a time
until the isolators lights come back on. The last circuit breaker you switched on has
the faulty circuit, or appliance connected to it.
Very rarely, even though all the circuit breakers (except the RCD) are switched off,
the isolator lights will remain on. In this case you will need to disconnect all
appliances, either by pulling out the plugs, or disconnecting any wired in appliances.
Do this one at a time, taking care to ensure that you don’t forget anything. As you
disconnect items, check the isolator lights. The last item you disconnect is the one
causing problems.
Model Gi-120/BK only

When you have traced the fault to a single appliance or circuit, it must then be checked for
earth leakage by a competent person.
Imprinted Leakage
Imprinted Leakage typically occurs when equipment
using a Switched Mode Power Supply Unit, (SMPSU),
is connected to your system.
Equipment utilising SMPSU’s include, Battery
Chargers, Computers, TV’s, Domestic Appliances,
Phone Chargers etc.
In our experience, battery chargers are often the cause
of imprinted leakage. CE regulations require that
equipment should not create this kind of interference,
but not all equipment is as “clean” as it should be.
Because of the way SMPSU’s operate, some of them leak power into the boat’s
earth wiring. This can cause the galvanic isolators light to come on, as the isolator
correctly detects the leakage.
Imprinted Leakage is traced in exactly the same way as for Mains Leakage.
However, when you track the problem down to an individual appliance, it may still
pass an Earth Leakage test. In that case, it’s likely that the problem is Imprinted
Leakage. Imprinted Leakage is often due to incorrect installation, but can also result
from design or manufacturing issues.
Pay close attention to earthing of equipment. Equipment is often installed
without adequate earth bonding. Please consult the equipment’s
installation manual, or contact the manufacturers for more information.
Earth bonding point
Model Gi-120/BK only

ONE (either) LED glowing
Disconnect
Start Battery Resolved? Check Alternator, Bilge Wiring, Battery Casings.
Reconnect battery, then disconnect all connected
circuits one at a time until resolved.
Y
N
Disconnect
Leisure Batteries
Resolved? Y
Check Alternator, Bilge Wiring, Battery Casings.
Then disconnect all connected circuits one at a time
until resolved.
N
Further testing
is beyond the scope
of this guide
This indicates a possibility of AC (mains voltage) leakage. Proceed with great care
Danger of electrical shock. If in doubt, please consult a qualified electrician.
Unplug every appli-
ance connected to a
socket in turn, until
LED's are extinguished.
Resolved? Y
The last item you unplugged was a likely
Cause of the fault. Rectify & re connect
Disconnect each AC
circuit in turn (using
circuit breakers where
fitted) until LED's are
extinguished.
N
Resolved?
The last circuit disconnected was a
likely cause of the fault.
Rectify & re connect
Y
N
Further testing
is beyond the scope
of this guide
BOTH LEDs glowing
Model Gi-120/BK only