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Waste Oil Heater => Waste Motor Oil => Topic started by: Russ on March 17, 2013, 11:00:30 am

Title: Ignitors
Post by: Russ on March 17, 2013, 11:00:30 am
Here is some information from Beckett's site:


IRON CORE TRANSFORMERS draw 120 VAC (Volts, Alternating Current) into their primary coil. The steel plates of the transformer core transfer the primary coil's 60 Hz magnetic field to the secondary coil. The secondary coil uses this field to produce a high output voltage of 10,000 VRMS open circuit (when there is no secondary current flowing) that has a frequency of 60 Hz.

ELECTRONIC IGNITORS receive 120 VAC and change it to DC (Direct Current) voltage inside. The DC voltage turns power transistors on and off very quickly, conducting current through the primary coil of its small internal transformer at a frequency of 15,000 to 30,000 Hz. The secondary coil of this special high frequency transformer produces a high voltage ignitor output that has a frequency of 15,000 to 30,000 Hz.

Remember: the ability of an ignitor to ignite oil depends on more than just high voltage - it depends on arc output current as well! Spark heat energy = voltage x current.

The electronic ignitor does not require extensive maintenance. However, there are areas to consider:

Just like an iron core transformer, an electronic ignitor is most simply tested by supplying it with 120 V input and observing whether it produces an arc. This may be done by looking or listening to see if there is an arc across the electrodes while the burner is running and the ignitor is energized. Secondly, the ignitor may be tilted back on its hinge and, when voltage is applied, the blade of an insulated screwdriver may be placed across the springs to test for an arc. NOTE: The cad cell will not permit the primary control to energize the ignitor if the cad cell senses light. Therefore, before you perform this test, disconnect one lead of the cad cell from the primary control, or remove the cell from its base. Remove power from the rest of the burner and disconnect the fuel supply from the nozzle line while performing this test. SHOCK HAZARD: Though this test is common industry practice, be careful not to physically touch any part of your body to the ignitor springs or anything metal that is touching the ignitor springs while the ignitor is energized. DO NOT use transformer testers to test electronic ignitors. Doing so will give you an inaccurate measurement and may harm the ignitor, the transformer tester, or both.

If an ignitor fails, it generally produces no arc at all. However, similar to an iron core transformer, an electronic ignitor can have a weak output arc. To test for this, perform the screwdriver arc test described above. Energize the ignitor and place the blade of the insulated screwdriver across the springs. Keeping the blade in contact with one of the springs, slowly pull the blade away from the other spring, drawing an arc from the spring to the blade. With a 110 V to 120 V input and no air flow across the arc, the ignitor should be able to maintain an arc with the screwdriver blade at least 3/4" away from the spring. If the ignitor is not able to sustain a 3/4" spring-to-spring arc, or if an arc drawn from one spring to the grounded baseplate is weaker than an arc drawn from the other spring to the baseplate, replace the ignitor.

Electronic ignitors have proven to be durable, effective ignition components. They have achieved wide acceptance in the oilheat industry. Hopefully, this bulletin has further acquainted you with important features, performance, and service aspects.