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How to Flash a Generator With a Battery? – Quick Fix!

How to Flash a Generator With a Battery
Written by Jamie Masterson

Sometimes, a generator will stop working. A low electrical or mechanical input may have caused this and the only option available is to restart the generator by passing a current through it.

The reason for flashing a generator is to restart it after it stops and the process is quite easy and requires simple tools without any special skills. Follow the steps below for flashing your generator.

Why Does a Generator Run Without Producing Electricity?

Errors or blockages in the excitation circuit

Identify the error in the circuit wiring and correct it.

Locate and reconnect the blocked excitation winding with a multimeter for blocked circuits. When a poor connection is the cause, the oxide layer on the surface needs polishing until smooth. This will help the bolt and nut connect firmly.

Worn brushes

Remove the brush assembly and examine it for damage, breaking, or sticking. Carbon brushes are rectangular components that insert into an assembly and pop in and out easily.

Defective capacitor

Discharge any remaining charge on the capacitor by removing it from the generator. Measure its charge with a multimeter. Capacitor readings must be within +/- 5uf of the rating indicated on the side. If not, contact a technician.

An excitation winding that has broken or grounded

Make sure the excitation winding is ground insulated by using a 500V ohmmeter. Identify the ground point, find and repair the broken winding using a multimeter.

A voltage regulator that does not work and needs replacing

The alternator cover of your generator needs removing. Unscrew the two spade connectors from the brush assembly.

Now, take out the screws securing the AVR in place. Detach the quick connector, attach the new AVR, and reassemble the unit as directed.

Lost magnetic residuals

The alternator has electromagnetic components that need a small amount of residual magnetism for priming to generate electricity.

There are several cases where residual magnetism becomes lost. For example, it ran out of gas with a load when left unused for a long time. Turning off the engine during a load can also be a cause

Poor connections

If connections are bad, clean any particles, debris, or obstructions, and secure everything.

Tripped breaker

Before starting the generator again, identify the cause of the breaker trip and remedy it.

Defective breaker

If you have low or no voltage, you have a defective breaker. A defective breaker is suspected if the voltage isn’t responding to the loads.

How to Flash a Generator With a Battery?

Step 1: Remove exciter fields

Voltage regulator exciter leads F+ and F- must get disconnected. Flashing a regulator without removing the field lead causes regulators to become damaged.

Step 2: Get rid of the persistent winding

Using the F+ and F- leads, measure the excitation field resistance. A continuous winding should display some resistance when you measure it. A reading of zero resistance indicates an open exciter field. Make sure that there are no paths to the ground.

Step 3: Associate the F+

A positive battery pole connects to F+

Step 4: Contact the negative lead

Hold the F- wire by the insulated end of the lead wire F- against the negative terminal. Hold for about three to five seconds, before removing. If there is an arc, the F- wire should get disconnected.

Step 5: Reconnect F- and F+

F- and F+ need reconnecting to the regulator. If the generator doesn’t build voltage, repeat the procedure.

About the author

Jamie Masterson

With decade-long experience as a generator technician, Jamie has worked with USA’s top generator manufacturers and suppliers as an independent contractor.

The long years of service to the industry has taught Jamie the ins and outs of troubleshooting, repairing, and maintaining all kinds of generators in home, industrial and outdoor settings.

Jamie thinks this platform is a great opportunity to share his tips and tricks with you so you can make the most of such power equipment for better living.

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