Middleby Marshall PS200 series - Manual (Page 15)

14
SECTION 3 - SERVICING COMPONENTS
Figure 15
Old-style pickup assembly
Figure 14
PS350-style pickup assembly
(used on early PS360)
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).
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