Middleby Marshall 60254 installation manual IV. Electric Supply for Electrically Heated Ovens

III.ELECTRICAL CONNECTION INFORMATION FOR PS740E-SERIES OVENS.

WARNING

Authorized supplier personnel normally accomplish the connections for the ventilation system, electric supply, as arranged by the customer. Following these connections, the factory-authorized installer can perform the initial startup of the oven.

Check the oven data plate (Figure 2-17) before making any electric supply connections. Electric supply connections must agree with data on the oven data plate.

NOTE: The electric supply installation must satisfy the require- ments of the appropriate statutory authority, such as the National Electrical Code (NEC), ANSI/NFPA70, (U.S.A.); the Canadian Electrical Code, CSA C22.2; the Australian Code AG601; or other applicable regulations.

A fused disconnect switch or a main circuit breaker (customer furnished) MUST be installed in the electric supply line for each oven; it is recommended that this switch/ circuit breaker have lockout/tagout capability. The electric supply connection must meet all national and local electrical code requirements. Copper is the recommended material for the electrical supply conductors.

IV. ELECTRIC SUPPLY FOR ELECTRICALLY HEATED OVENS

Power requirements for electrically heated ovens are usually 208 - 240VAC, 3-phase, 4-wire (3 ‘hot’, 1 ground), although ovens built for export can have power requirements of 380VAC and 480VAC. (These ovens have a 5-wire system.) A 2″ (51mm) diameter cutout/hole in the back of the machinery compartment provides access for the electrical supply connections. Using flexible cable(s) for the electrical power supply conductors requires a 2″ (51mm) strain-relief fitting (not furnished) to en- able safe access to the terminal block from which oven power is distributed.

The supply conductors must be of the size and material (cop- per) recommended to provide the current required; (refer to the data plate for the ampere specifications). The electric current rating for each conductor supplying a PS740E-Series Oven must comply to local and national codes.

Typical specifications for each PS740E-Series Oven are 208V or 240V, 3-phase, 4-wire, 60-ampere, 34.4kW. A PS740E-Series Double Oven (Figure 1-2) installation would require two 60-ampere service connections, one for each oven; the 34.4kW power consumption also doubles for such an installation to 68.8kW.

The 208V or 240VAC electrically heated oven uses two legs of the supplied power to provide 208V or 240VAC power for the oven control circuitry.

Electrical Junction Box (One per oven cavity)

	Figure 2-18. Utility Connection Locations for Elec-
Figure 2-17. Typical Electric Oven Data Plate	tric Ovens
17	P/N 60254 September 28, 2012