Rewired Condenser with a Buck-Boost Transformer

Eric Mele shows us a condenser that he has adjusted. He also added buck-boost transformers in the “boost” configuration. The incoming power supply is low, so the boost configuration increases the voltage from primary to secondary.

The condenser fans have been rewired. In the current configuration, the failure of one fan won’t take the other fans out. However, our main goal is to prevent fan failure altogether.

We have moved the circuit board over to make room for the buck-boost transformers. Eric installed two transformers and drew out the schematic on the panel so that future technicians can understand how he wired those transformers. The left of the schematic represents the low-voltage incoming power, and the right side shows the high voltage.

From line 1 to line 3, we only measure 201 volts on our incoming power. From line 1 to line 2, we measure 197 volts, and line 2 to line 3 measures 202 volts. However, with the help of the transformers, line 1 to line 2 boosts up to 222 volts. Line 2 to line 3 measures 217 volts with help from the transformer, and line 1 to line 3 measures 221.

We also have a control transformer tied into the low-voltage side of the system, and we get 200 volts to that transformer.

Anytime you make changes to the wiring of a condenser, keep the old wires with the system in case anything needs to be rewired. Create a schematic diagram as Eric did and make sure you provide all the important information that the next technician needs to know.

Our overall goal is to improve motor longevity. Motors can be expensive, so we want to minimize preventable costs and equipment casualties as much as we can.

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