Middleby Marshall PS220, PS570, PS360 Removing elements, 141, Individual element electrical data

Figure 78

Fan shroud removed

4.Heater specifications

•PS200-series electric ovens use six individual heat- ing elements.

•208V elements are used for ovens with a 208V supply.

•240 volt elements are used for ovens with a 220, 230 or 240V supply. 240V elements are also used on ovens with a 416V or 480V supply (connected in se- ries).

•380V elements are used for ovens with a 380V supply.

•All heaters are connected in Delta.

•Each heating element is stainless clad and has a 3”/76mm cold (unheated) end next to the connect- ing leg.

•Individual element electrical data

Volts	Watts	Ohms	Connection
208V	4500W	9.6W	Parallel
220V	3781W	12.8W	Parallel
230V	4133W	12.8W	Parallel
240V	4500W	12.8W	Parallel
380V	4500W	32.2W	Parallel
416V	3380W	12.8W	Series
480V	4500W	12.8W	Series

5.Checking the Heating Elements

The most common problems encountered with electric heaters are:

•Open or bad connections.

•Open, shorted or grounded heating elements.

To troubleshoot the heating elements, disconnect all leads at the back wall and check each element with a digital multimeter set to Ohms (W). Correct ratings are shown in the table in the preceding section. Zero read- ing on the ohm scale indicates an open or shorted ele- ment.

SECTION 3 - SERVICING COMPONENTS

It is also possible to check for an open element using an ampmeter. Any current through the element indi- cates that the element is not open.

6.Changing Heating Elements

NOTE: Wires going from the mercury contactor (or solid state relays, as appropriate) to the heating ele- ments are rated at #12 gauge TAGT, 482°F/250°C. DO NOT, under any circumstances, use a wire of lesser rating or quality.

NOTE: All lugs and connections are rated at 600°F/ 316°C. All heating element connections are double- nutted.

To remove the element:

•Remove the blower belt.

•Remove the 12 electrical lead connections to the heaters at the back wall.

•Remove the 12 bolts that hold the rear oven panel to the body. Once removed, DO NOT lay the panel on either its front or back side. This can damage the heating elements and blower fan. The panel should be kept upright as shown in Figure 78.

•Remove the fan shroud.

•Remove the screws at both ends of the element and pull the element straight out. See Figure 79.

•When replacing the rear oven panel, be sure to use a high-temperature never-seize lubricant on the 12 bolts that hold the panel in place.

Figure 79

Removing elements

Mounting s c r e w s

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