QUESTION: Will
surge capacitors on a motor effect the Meg-Alert?
ANSWER: Most surge capacitors have bleed resistors
connected to ground that effect the Meg-Alert readings.
The capacitors have to be replaced with the type that does
not have bleed resistors in order for the Meg-Alert reading
to be correct. (GE makes a capacitor with no bleed resistors).
QUESTION: Can
you use the MEG-ALERT on A.C. and D.C. motors?
ANSWER: Yes, the MEG-ALERT is designed to test both
A.C. and D.C. equipment
QUESTION: Can you use the
MEG-ALERT on synchronous motors?
ANSWER: Yes, the brushless type synchronous motors
will only require (1) MEG-ALERT. The brush type synchronous
motors can use (2) MEG-ALERTS, one on the stator and one
on the rotor.
QUESTION: Can you use the
MEG-ALERT on motors when they are running?
ANSWER: No, The MEG-ALERT is designed to test equipment
that is not in operation and prevent an insulation failure
on start up.
QUESTION: We have lightning
arrestors and power factor correction capacitors in our
motor control centers. Can we still use the MEG-ALERT?
ANSWER: Yes, providing that there are no direct grounds
on the motor side of these components. A time delay is built
into the MEG-ALERT systems to allow for some charging effects
in such cases. Good lighting arrestors and power factor
capacitors do not effect the Meg-Alert readings.
QUESTION: Can I use more
than one test voltage per MEG-ALERT?
ANSWER: No, the MEG-ALERT can only provide one test
voltage value per unit.
QUESTION: Where is the MEG-ALERT
normally located in a typical circuit?
ANSWER: The MEG-ALERT in connected to one of the
phases, at the motor contactor or generator breaker and
to the equipment ground, and is generally mounted in or
next to the motor control center or generator switchgear.
The medium voltage models need to have the Meg-Alerts located
in the H.V. compartment of the control cabinet or in a separate
enclosure.
QUESTION: Can you automatically
test the insulation resistance for submersible pumps?
ANSWER: Yes, the MEG-ALERT will check submersible
pumps and the underwater cables from the starter to the
motor.
QUESTION: Can you automatically
test the insulation resistance on grounded generator Systems?
ANSWER: Yes, by installing our ground interrupter
on each grounded generator equipped with a MEG-ALERT, to
remove all grounds before automatically testing insulation
resistance. Two safety circuits are provided to ensure that
the ground is re-connected before the generator can produce
voltage.
QUESTION: My motors run
24 hours a day. How can MEG-ALERT benefit me?
ANSWER: Most equipment that operates 24 hours a day
is critical and can not afford lengthy downtime, however
preventative maintenance testing is required. The MEG-ALERT
allows you to perform your PM test with the minimal amount
of downtime and expense and can be done quickly during any
normal interruption that may occur with this type of equipment.
Manual testing would not normally be possible in this situation.
QUESTION: Can you user the
MEG-ALERT as a manual system?
ANSWER: Yes, the single MEG-ALERT units can be equipped
with a push button test feature to eliminate the auto mode
or the multiple units can simply be left in the manual position.
QUESTION: Can you set multiple
set points (trip points) with one unit?
ANSWER: Yes, some models are available with two set
points: a pre-alarm and fault alarm. The first trip point
is a pre-alarm to indicate early insulation breakdown. The
second trip point is a fault alarm that indicates that corrective
measures should be taken to prevent an impending failure.
QUESTION: Can the MEG-ALERT
be used on motors or generators with low current winding
heaters?
ANSWER: Yes, in some cases it may be necessary to
install an isolation transformer on the heater input voltage
circuit.
QUESTION: Can you set different
alarm settings or test voltages on each motor or generator
on the multiple model MEG-ALERT?
ANSWER: No, one common alarm setting and testing
voltage is used for all test points on the multiple model
MEG-ALERT.
QUESTION: Is there any deterioration
of the insulation by continuously testing at a rated voltage?
ANSWER: No, the unit will not cause an insulation
breakdown because it uses a nondestructive D.C. test voltage
with current limiting to a maximum of 350 micro amps. Our
patented voltage/current safely circuitry also protects
dead grounded equipment from being harmed.
QUESTION: Will the MEG-ALERT
harm any of the solid-state control equipment (voltage regulator,
variable frequency drive, etc.) in my generator or motor
control panel?
ANSWER: No, the MEG-ALERT tests between the "B" phase
and the ground. Thus, there is no potential for high-test
voltages on control equipment, unless they are connected
between a phase and ground. On 240 VAC generating systems,
it may be necessary to install isolating transformers to
protect control equipment.
QUESTION: On a 4160 volt
system, how are maintenance personnel protected from high
voltages at or coming from the MEG-ALERT unit?
ANSWER: The GP2500 and GP5000 MEG-ALERT systems are
fused and current limit protected, both on the output from
the MEG-ALERT and from the motor operating voltages, for
personnel safety. Remote and local "power on"
LEDs are provided with the MEG-ALERT systems as well as
a latching power on/off switch to indicate and remove power
from the MEG-ALERT system. The Meg-Alert when wired correctly
is powered down during normal lock and tag out of the power
disconnect switch.
QUESTION: How far can a
motor or generator be from the MEG-ALERT unit?
ANSWER: The MEG-ALERT can be up to 1,000 ft. from
the equipment being tested as long as the test lead is wired
with a minimum of 18 AWG wire.
QUESTION: How are maintenance
personnel made aware that the equipment is being automatically
tested by the MEG-ALERT?
ANSWER: Remote flashing LED assemblies can be mounted
on the door of the control cabinet or motor starter bucket
and warning labels are provided with the MEG-ALERT to be
mounted on the equipment as well as the switchgear doors.
QUESTION: Will
damage occur to the MEG-ALERT if the "motor run" control
signal fails and the MEG-ALERT stays in the circuit with
the operating voltage present?
ANSWER: No, the MEG-ALERT high
internal impedance protects the system and allows the test
voltage to trip out the MEG-ALERT on a fault alarm after
the service ground is detected.
QUESTION: Can
you use a Meg-Alert on motors powered by a variable frequency
drive or solid state soft start?
ANSWER: Yes, providing that an isolation contactor
is installed to isolate the motor from the VFD of soft start.
If there is no contactor in the system one can be provided
with the Meg-Alert system. The older type auto transformer
soft starters do not affect the Meg-Alert.