Middleby Marshall PS555, PS570, PS200, PS220 manual PS350-style pickup assembly used on early PS360

SECTION 3 - SERVICING COMPONENTS

B. Part Number Reference - Pickup Assemblies

1.PS350-style pickup assembly or old-style pickup as- sembly (see Figures 14-15). These parts use the same part number. They are no longer available from the factory, but may still be stocked by some service agen- cies.

P/N Description

28074-0005 Pickup assembly, PS350-style or old-style

2.Current-style pickup assembly (see Figures 16-17)

P/N Description

27170-0263 Pickup assembly, current

C. Preparing to Service the Speed Controller

NOTE: To properly service this equipment, you must use a digital meter. An analog meter will not work.

1.Before troubleshooting the conveyor speed controller, check the following:

a.Conveyor belt is tight.

b.Drive chain is tight and aligned.

c.Set screws on drive sprockets are tight.

d.Axial fan(s) are running and clean of dust and de- bris.

e.Motor and pickup wires are secure at the Conveyor Terminal Block (location of the block varies by oven model).

f.Wire connections on conveyor speed control mod- ule (including the ribbon cable to the thumbwheel/ display unit) are secure.

2.Check the pickup for the following (see Figures 14-17):

a.Pickup is secure.

b.Magnet is not cracked or chipped.

c.Magnet is not rubbing on plastic housing.

d.Mounting bolt is not worn or bent.

e.Pickup bearing in good condition.

f.On PS350-style pickup (Fig. 14), gap between magnet and Hall Device is spaced approximately 1/64”-1/32” (0.4-0.8mm, or a business card thick- ness).

Figure 14

PS350-style pickup assembly

(used on early PS360)

Figure 15

Old-style pickup assembly

14