DynaGen ES52, Инструкция по установке и эксплуатации

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Operating & Installation Manual for the ES52 Engine Controller
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3. Step-Down Transformer Use On Speed Sensing Cable With Inverter Systems
In some applications engine controllers are used on generators where there is no utility
connection and inverters are used to provide AC power instead of a utility. Inverters can produce
harmonics that can cause small AC signals to appear on wires that are near any power lines being
fed by the inverter. If the generator output wires are located close to a line being powered by an
inverter, a small AC signal can appear on the generator output lines when the inverter is on. This
signal can cause the engine controller to react as if the generator is running if the speed sensing
wires are connected to the generator output lines. This small AC signal can cause the controller
to appear to have a Low Oil Failure when the remote start contacts are closed or the controller is
put in the manual/test mode. The controller may think the generator is already running and
immediately check to make sure there is oil pressure. Since the engine really hasn’t started yet,
there is no oil pressure and the controller sees a low oil fault. This is seen as the Oil LED turning
on solid even before the engine starts to engage the starter.
Without this false speed signal the controller will not look for oil pressure until the engine has
started to run and the crank disengages if oil verification is disabled. Simply installing a small
transformer between the generator output and the speed sensing terminals on the controller can
eliminate this false speed signal. This transformer should be rated for 120 or 240 volts on the
input or primary coil (depending on the generator output voltage you are using for speed
sensing), and have an output voltage of around 12VAC on the secondary of the transformer. The
two wires from the secondary of the transformer are connected to the two wires of the speed
sensing terminals on the ES52 controller. The step-down transformer acts to reduce the false
speed signal on the line to a level that the engine controller will not recognize as the engine
running. A common size transformer that would serve this purpose would be 24VA.