Middleby Marshall PS224 PS310 PS570/570S blower configuration, PS555/570G blower configuration

SECTION 3 - SERVICING COMPONENTS

A. PS555/570-series ovens

All PS555/570-series ovens are equipped with two 1hp blower motors. Each motor indirectly drives a pulley on the shaft of a blower wheel with a fan belt.

Two main designs exist for the PS555/570 blower fan sys- tem:

•PS570/570S design. In this version, the pillow block bearings for the blower wheel shaft were mounted up- right, on brackets that were parallel to the fan belts. See Figure 42.

•PS555/570G design. In this version, the pillow block bearings are mounted with the grease fittings pointing in towards the center of the oven. See Figure 43.

The two designs share many common parts, including blower wheels, motors, and bearings. From a service standpoint, the major difference is the size of the pulleys and the length of the belts.

Blower motors on all PS555/570-series ovens are rated for

208-240V, single-phase, and are protected by:

•A built-in thermal overload protection device.

•Two 15A fuses or 15A circuit breakers. Refer to Figure 44 for the location of the fuses/breakers.

In addition, each blower fan is protected by an air pressure saftety switch that prevents the burner/heating elements from activating if the fan is not rotating. See Air Pressure Safety Switch on Page 81.

Figure 42 - PS570/570S blower configuration

Belt

Blower

motor Direction

of rotation

Pulley

Bearing	Blower Pulley	Blower wheel
	shaft	(inside oven)

Figure 43 - PS555/570G blower configuration

Belt

Blower

motor

Pulley

Bearing	Blower Pulley	Blower wheel
	shaft	(inside oven)

Figure 44 - Fuse/circuit breaker locations

		PS555 (current),
PS570/570S:	PS555 (early):
		PS570G: 15A
15A fuses located on	15A breakers located
		breakers located on
left side of machinery	inside left blower
		right side of machinery
compartment	motor compartment
		compartment

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