Lighting in Design

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Otto Horlacher of Giantlight has designed
what he believes will be a welcome solu-
tion to the ‘dropped neutrals’ frequently
experienced during the installation of LEDs in the
construction phase of a building.
A dropped or floating neutral effectively occurs
when the grounded conductor or neutral wire is
somehow disconnected from the original source
to the load. It is, according to Horlacher, a common
problem that occurs when electricians on site are
still busy fitting the electrics but proceed with the
installation of the light fittings nevertheless.
The electrician makes the relatively easy error
of mistaking one of the phases for neutral and in
so doing creates a voltage of anywhere between
270 and 380 instead of the usual 230 V. Dropped
neutrals are disastrous for LEDs and it is usually
the lighting supplier who bears the brunt of the
fault as it is difficult to ‘prove’ the mistake once
the electrician realises what has happened and
fixes the connection.
Higher than normal voltage supply on control
gear designed to operate at voltages not exceed-
ing 230 V, or sometimes even 220 V, will result in
premature failures. Control gear that can handle
and withstand 380 V is obtainable, but it comes at
a cost and is not readily available.
Horlacher is confident that his company will soon
be in a position to supply a range of LED engines
that can operate from 180 V to 380 V without be-
ing damaged in any way. The robust design will be
ideal for areas, such as certain districts north of
Pretoria; Alrode; and others, where the ‘normal’
supply voltage can often exceed 245 V.
For about a year, he has been working with an
electronics company to find a solution specifically
for LEDs and he believes that he has found one
that cannot only withstand 380 V but can function
quite comfortably at that voltage.
Working with a test board, Horlacher demon-
strated the product by stepping up the transformer
from 230 V to 380 V and noting the reaction by
measuring the onboard temperature, current and
voltage. Essentially, the system remained stable
where, normally, 380V onto any device would blow
the power supply.
He explains, “Preliminary tests
(exceeding 100 hours at 380 V)
indicate that the LED engine
we have created can op-
erate indefinitely – at
voltages way higher
than 230V – as it is self-
regulating. The most
important device, the
current regulator (the brain of the system), has a
temperature threshold – if it reaches that threshold
it automatically reduces its own current output to
protect itself and, in so doing, protects the LEDs
as well.
“Furthermore, the ‘onboard’ current control to
the LEDs remains stable to within 20%. For ex-
ample, if the LEDs are operating at let’s say 50%
of their rated maximum current, at 230V ac in, then
at 380 V ac in, the current only increases by 20%;
still well below the LED’s maximum threshold.Then
if the LED PCB begins to get warm, the constant
current regulator throttles back to further protect
the LEDs.”
What makes the new system even more appeal-
ing is the fact that there is no external driver and
all the technology is onboard. As Horlacher says,
“You buy the board, put it in your light fitting and
connect 230 V to it. You do not use a driver at all –
everything is computed into the board. So not only
is all the relevant technology onboard, but the board
remains stable and functions at 380 V”.
The onboard LED engines are also dimmable
with normal leading edge technology (subject to
verification by Giantlight of the dimmer manufac-
turer’s equipment).
Horlacher notes that normal thermal and other
LED luminaire manufacturing considerations still
need to be adhered to.
Giantlight has been at the forefront of LED
lighting technology in this country for a number of
years and has established a name for itself for the
design, manufacture and installation of compre-
hensive lighting solutions.The company intends to
introduce its new LED engine to the South African
lighting industry early in 2015.
Giantlight:
Tel. +27 11 704 1150
LED engine stable at 380 volts
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