25.5 Dual-Voltage Motors Dual-voltage motors are manufactured to operate on either of two supplied voltages. For example, the voltage rating on the motor data plate 25.4.6 Changing Motor Types It is possible to add start components to a hermetic compressor’s PSC motor to convert it to a CSCR motor. The procedure is sometimes necessary when the compressor’s PSC motor has difficulty starting, which is not unusual with resi- dential central air conditioning systems. Selecting a properly sized capacitor and relay is critical for proper operation. Sizing information is available from the local dealer or compressor manufacturer. Most manufacturers of compressors using PSC motors furnish a hard start kit for their units’ motors. The kit consists of a start capacitor and relay, along with complete instructions for installation. See Figure 25‑40. The model and serial numbers of the motor/compressor are needed to obtain the correct kit. Figure 25‑41 shows a hard start kit designed to work on multi-sized compressors. This kit should be used as a temporary fix. If the compressor needs a hard start kit, get the one from the compressor manufacturer that is specifically designed for that compressor. Goodheart-Willcox Publisher Figure 25‑39. A tester made specifically for use with capacitors helps the technician quickly diagnose problems. A B Images courtesy of Johnstone Supply Figure 25‑40. Hard start kits for adding on to a com- pressor for greater starting torque. A—Used on fractional horsepower compressors. B—Used on larger horsepower compressors. Goodheart-Willcox Publisher Figure 25‑41. A multi-compressor quick add-on hard start kit. Chapter 25 Motors 507 Copyright Goodheart-Willcox Co., Inc.