Middleby Marshall PS360 Conveyor Speed Bake Time, Time of Delivery, Belt Time, Iv. Oven Capacity

SECTION 2 - AIR FLOW AND HEAT TRANSFER

IV. OVEN CAPACITY

Oven capacity is generally not a service issue. However, when reporting a service problem, customers may use terms relating to capacity, such as bake time, belt time, time of delivery, etc. This information is provided as a reference for understanding these terms.

A.Conveyor Speed and Bake Time

Middleby Marshall conveyor ovens display the Conveyor Speed on the Thumbwheel (or on the display of the Digital Speed Controller, as appropriate for the oven model). Conveyor Speed is also called Bake Time.

Conveyor Speed (Bake Time) is a leading edge to lead- ing edge measurement. That is, it is the elapsed time from the leading edge of the product entering the bake chamber to the leading edge of the product leaving the bake chamber. See Figure 9.

B.Belt Time

Belt Time is a measurement used by several custom- ers. It is a trailing edge to trailing edge measurement. That is, it is the elapsed time from the trailing edge of the product entering the bake chamber to the trailing edge of the product leaving the bake chamber. See Figure 10.

Note that belt time is equal in length to conveyor speed (bake time), although the time is measured during a different period of the baking process.

C.Time of Delivery (TOD)

Time of delivery (TOD) is a leading edge to trailing edge measurement. That is, it is the elapsed time from when the leading edge of the product enters the bake cham- ber to when the trailing edge of the product leaves the bake chamber. See Figure 11.

Figure 9 - Conveyor Speed (Bake Time)	Figure 10 - Belt Time
Conveyor Speed	Belt Time
(Bake TIme)

Direction of			Direction of
Conveyor Travel	Leading edge	Trailing edge	Conveyor Travel
	of product	of product

Figure 11 - Time of Delivery

Time of Delivery

	Direction of
	Conveyor Travel
Leading edge	Trailing edge of
of product	product

D. Formulas for Determining Time of Delivery (TOD) and Oven Capacity per Hour

1. Time of Delivery (TOD)	Conveyor Speed
Time of Delivery (TOD) =		x (Bake Chamber Length + Product Diameter)
	Bake Chamber Length
Example: PS570S Oven, 7:00 Bake Time, 16” Product Diameter =			7 mins.		x (70” + 16”) = 8.6 mins. (8:36)
				70”

2. Oven Capacity/Hour	(Bake Chamber Length + Product Diameter) x Bake Chamber Depth				60 min./hr.
Oven Capacity/Hour =				x
	Product Diameter²				TOD
Example: PS570S Oven, 7:00 Bake Time, 16” Product Diameter =		(70” + 16”) x 32”	x 6.98 = 75 pizzas/hr.
		256 in.²

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