Yamaha EF4500iSE - Inverter Generator Theory & Diagnostics Manual Download

Page: 32 / 218

1-28

Yamaha Generator Theory & Diagnostics Guide

Most generator test sets also feature a frequen-
cy meter to enable you to make that adjust-
ment.

Another excellent use for the generator test set,
which very often becomes a major problem in
customer satisfaction, is for the proper selection
of a generator for a given application.

If there is any question as to the amount of cur-
rent that a certain appliance or a combination of
tools  will  require,  all  the  guess  work  can  be
eliminated  by  plugging  the  generator  test  set
into an external power source with high amper-
age  capabilities  and  then  plugging  the  appli-
ance or tools into the generator test set.

The generator test set’s amp meter will not only
tell you the required amount of current for nor-
mal operation, but will also tell you what the
start up current requirements are.

Start up current requirements are an often over-
looked step in proper generator selection and
should always be taken into consideration.

You will need to take the start up amperage plus
a cushion, to determine the generator size. The
cushion will allow for the possibility of future
requirement increases.

The  customer  will  be  much  happier  with  your
dealership if you were able to foresee his future
needs.  Especially  when  his  needs  do  change
and  he  would  have  had  to  purchase  another
generator, if you had not made him aware of that
possibility.

Hertz (Hz) Meter

The hertz meter is used to properly set the fre-
quency. U.S. applications will be 60 Hz adjusted
by increasing or decreasing engine rpm.

Pulse Tachometer

A tachometer is used to set the rpm on all gaso-
line powered models.

Special Diagnostic Tools

Utilizing the correct diagnostic tool for the job is
critical to our main goal, Customer Satisfaction.
Having the correct tools will ensure that the problem
is

fixed right the first time.

There are 5 important

diagnostic tools the Service Department should
have to properly diagnose and repair most Inverter
and Conventional generators.

Load Bank Tester /
Generator Test Set

The  load  bank  main  use  is  to  duplicate  prob-
lems,  and  verify  the  generator  works  properly
after  a  repair.  It  can  apply  an  adjustable  load
between 1-50amps. Many generators are capa-
ble of producing large amounts of power, so it is
necessary to use a tool to create a large, mea-
surable load to simulate any output issues. Heat
guns,  drills,  fans,  and  grinders  are  not  good
diagnostic tools as there is no way to measure
and  maintain  a  large  load. As  a  dealer  techni-
cian it is difficult to determine exactly how much
load  you  are  applying  when  not  using  a  load
bank tester. The load bank can also be used as
a  sales  tool  to  determine  if  a  generator  has
enough capacity to meet the customer’s needs.

Generator Test (Load Bank) Uses

Typically, the only way to test the generator if
you don’t have a load bank, is to plug some type
of tool into it and turn it on. If it operates the tool,
you assume that it’s making electricity and must
be fixed.

This is not necessarily true .

Just because one appliance works, it does not
guarantee  that  the  unit  will  work  for  the  cus-
tomer. If the customer gets the unit home or to a
construction site and immediately finds out that
it  still  does  not  work  for  his  application,  your
Customer  Satisfaction  level  with  this  customer
will be in serious jeopardy.

This can be easily avoided by the use of a gen-
erator test set. The generator test set will make
it possible to select the amount of current used
by a particular customer under real world condi-
tions.

You can even select the amount of current for a
given generators rated output and let it run for
awhile at that power load. If it passes that test
you are practically guaranteed that it will work
for your customer.