TP-6953 7/19130 Section 7 Troubleshooting
Step Potential Cause
Explanation Troubleshooting
Fault: Generator Voltage Average Line to Line: High Warning
1 Metering calibration
issue
All the generators on the paralleling bus attempt to control to the same voltage.
If one has incorrect calibration, it may see this voltage as a much higher level
than the other generators, resulting in a protective relay trip.
Verify the controller is measuring v oltage accurately. If not, re-calibrate it.
2 Voltagedropon
generator connection
leads
If the generator is sourcing high current through too small of output leads, the
voltage drop in these cables may require the generator to run at an increased
voltage to supply the necessary current to the paralleling bus.
Install oversized connecting leads for the generator to minimize voltage
drop between the generator and the paralleling bus.
3 Attempting to operate
a generator in
base-load mode while
it is connected to a
variable load
The speed bias and voltage bias control real and reactive load in base-load
mode against a source with a nearly constant frequency and voltage (such as a
utility source). If the generator is disconnected from the utility source, the speed
and voltage will deviate to either extreme of the bias range, depending on the
target load and the actual load.
Install contacts in series with the base-load mode input to the controller
which are disconnected when the utility source is disconnected from the
paralleling bus.
Fault: Generator Voltage Average Line to Line: Low Warning
1 Metering calibration
issue
All the generators on the paralleling bus attempt to control to the same voltage. If
one has incorrect calibration, it may see this voltage as a much lower level than
the other generators, resulting in a protective relay trip.
Verify the controller is measuring v oltage accurately. If not, re-calibrate it.
2 Attempting to operate
a generator in
base-load mode while
it is connected to a
variable load
The speed bias and voltage bias control real and reactive load in base-load
mode against a source with a nearly constant frequency and voltage (such as a
utility source). If the generator is disconnected from the utility source, the speed
and voltage will deviate to either extreme of the bias range, depending on the
target load and the actual load.
Install contacts in series with the base-load mode input to the controller
which are disconnected when the utility source is disconnected from the
paralleling bus.
Fault: AC Frequency: High Warning
1 Attempting to operate
a generator in
base-load mode while
it is connected to a
variable load
The speed bias and voltage bias control real and reactive load in base-load
mode against a source with a nearly constant frequency and voltage (such as a
utility source). If the generator is disconnected from the utility source, the speed
and voltage will deviate to either extreme of the bias range, depending on the
target load and the actual load.
Install contacts in series with the base-load mode input to the controller
which are disconnected when the utility source is disconnected from the
paralleling bus.
Fault: AC Frequency: Low Warning
1 Attempting to operate
a generator in
base-load mode while
it is connected to a
variable load
The speed bias and voltage bias control real and reactive load in base-load
mode against a source with a nearly constant frequency and voltage (such as a
utility source). If the generator is disconnected from the utility source, the speed
and voltage will deviate to either extreme of the bias range, depending on the
target load and the actual load.
Install contacts in series with the base-load mode input to the controller
which are disconnected when the utility source is disconnected from the
paralleling bus.
Fault: Generator Total Real Power: High Warning
1 Continuous overload The generator breaker will trip to protect the generator from damage due to
excessive loads.
Ensure that the load is low enough for a single generator to support it.
Fault: Generator Total Real Power: Low Warning
1 Loss of fuel pressure The generator breaker will trip to prevent generator operation. Otherwise,
power could be absorbed from other generators causing potential damage to
the fuel system by operating without lubrication.
Ensure that the generator has sufficient fuel to support load. Connect a fuel
level sensor and place Generator Management in Fuel Level Equalization
mode.
2 Quick ramp rate
settings
The real power may overshoot when in a real power control situation such as
base load or system control.
It may be necessary to adjust the load control gains.
3 Different sized units or
units of different fuel
types.
The real power may overshoot when in a real power control situation such as a
load ramp or a quickly changing customer load.
It may be necessary to adjust the kW load sharing gains.
4 Different engine speed
adjust settings
Setting the Engine Speed Adjust parameter high on a generator will result in
that generator providing more real power than the other generators. It is
possible to drive the other generators offline in light loading conditions.
Set the engine speed adjustment similarly on all generators.
To Next Page
Loading...
