illustration that demonstrates checking a transformer with an ammeter . The procedure for this test is as follows :
• Shut off power and remove transformer leads from circuit . Supply power to transformer only .
• Place clamp-around ammeter on one of the power leads to the transformer . The reading obtained should be within 5 % of the transformer draw .
Figure 5-16
Another tester is shown in Figure 5-16 . Although more expensive than others and limited only to the testing of ignition transformers , it can prove to be an invaluable tool . It is produced by Dongan Transformer .
The testing of electronic ignitors is a little bit more complicated . Although the screwdriver test , as shown in Figure 5-13 , is permitted by most manufacturers , not all of them encourage it or endorse it . Even if the OEM does allow it care must be taken not to directly short the terminals without a spark between them for a long period of time . In many cases it may short out the ignitor and destroy its internal circuitry . Keep in mind that ignitors are not merely a pair of coils , but rather a complex electronic device made up of several electronic circuits .
Figure 5-17
The first basic test for ignitors is to place an ohmmeter across the ignitor output terminals with the power off and measure the resistance from each ignitor post to ground , Figure 5-17 . Normally the ignitor is considered good if the resistance from each post to ground has no more than a 10 % difference . Each OEM is different and they should be consulted for the proper output range . Verifying a short between the ignitor case ground and true ground is also a major part of this test .
Another test that can be done and is approved by most manufacturers is to bring the ignitor output terminals to within ½ to ⅝ of an inch apart and turn on the power , Figure 5-18 . A strong blue spark should be generated . Another trick is to let it spark for a
Figure 5-18
Figure 5-19
few minutes , five to ten in most cases , and see if the spark changes , if it does , I would replace the ignitor . In addition , if you really want to put the ignitor under-the-gun , so to speak , place a milliammeter in series with the hot line going to the ignitor and turn it on , Figure 5-19 . Again , the reading should stay steady and not vary for at least five minutes with a strong spark throughout the test .
Many testers for all of these devices are questionable in their results . Many are simply looking for a voltage range , some merely a voltage presence , some are looking for a radio frequency ( RF ) field that can also be generated by nothing but a fluorescent lamp . Check into this before you spend your money , but please invest in a multimeter , it is money well spent .
Finally , the most important tests of all . Before working any of these tests verify the incoming voltage to be 120 volts AC incoming and that all of the grounding on all of these circuits be properly checked and found to be present . See ya ! l FON George Lanthier is the owner of Firedragon Academy . His website can be found at www . FiredragonEnt . com which includes a link to Firedragon Academy ’ s Facebook page .
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