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6
BREAD BAKING APPLICATION
Loaves of bread are being baked in a continuous baking oven. It has been
determined that 10 minutes and 30 seconds is normally required for a loaf to
progress through the oven (this provides enough time for the loaves to be
baked). An RPGC, with 60 PPR, is attached to one of the conveyor belt shafts.
When the conveyor belt moves at the 10 min.-30 sec. rate, the shaft turns at 35
RPM. An APLPT5 is used to display the value of 10 min. and 30 sec. Using
the formula, the required DIP switch settings are obtained.
PPS = 60 PPR x 35 RPM = 2100 PPM ÷ 60
DMIT = D.R. x P.P.S.
PPS = 35
= 630 x 35
DR = 10 min. & 30 sec. (convert min. to sec.)
DMIT = 22,050
DR = (10 min. x 60) + 30
DMIT = 22,050 ÷ 10
*
DR = 630
DMIT = 2,205
* A scale multiplier of 10 is selected because a value greater than 16,383 is
required.
DIP switch 12 . . . . . -
2048
Needed =
157
DIP switch 8 . . . . . -
128
Needed =
29
DIP switch 5 . . . . . -
16
Needed =
13
DIP switch 4 . . . . . -
8
Needed =
5
DIP switch 3 . . . . . -
4
Needed =
1
DIP switch 1 . . . . . -
1
Therefore, DIP switches 1, 3, 4, 5, 8, and 12 must be turned “ON”. Also, DIP
switch 4 on the side panel must be set “ON” to get a multiplier value of 10.
DISPLAY MULTIPLIER SELECTION PROCEDURE
The APLPT/PBLPT has a Display Multiplier Selection range from 1 to
16,383. For the minimum scaled reading, the X1 DIP switch would be set to
“ON”. For the maximum scaled reading (16,383 times the measured time
between input pulses), all of the rear panel DMIT DIP switches would be turned
“ON”. Therefore, a specific Display Multiplier Increment Total is achieved by
adding up the appropriate individual display multiplier values.
Also available are four scale multiplier (SM) values of X1, X10, X100, and
X1000, which are controlled by DIP switches 4 and 5 on the side of the unit.
The X10, X100, and X1000 scale multiplier values can be used when the
required DMIT exceeds 16,383.
Note: Always use the smallest SM value
possible
. Below is a formula to compute the DMIT.
Note: This same basic
formula applies to all units.
However, for the APLPT5/PBLPT5 the D.R. must
be converted to a base unit of measurement.
DMIT = D.R. x P.P.S.
DMIT = Display Multiplier Increment Total
DR = Desired Reading (In hrs., mins., sec., days, etc.)
PPS = Pulses Per Second (input)
NOTES:
1. For the APLPT5/PBLPT5, the display value must be converted to its base
units. To do this, multiply the value to the left of the dash by 60 and add it to
the value to the right of the dash.
2. If the required DMIT value exceeds 16,383, then a scale multiplier value
greater than 1 will be needed. But always use the smallest SM possible.
EXAMPLE 1 (for APLPT4):
DESIRED READING = 18 minutes
PULSES PER SECOND = 450 pulses per second
DMIT = 18 x 450 P.P.S.
= 8100
DMIT = 8100
The required DMIT does not exceed 16,383, therefore, use a value of 1 for
the S.M.
The appropriate display multiplier switches (which together add up to 8100),
are then set to “ON”. Start by selecting the first increment which is greater than
half the desired DMIT, and add subsequent increments that are more than half
the difference needed.
DMIT = 8100
DIP switch 13 . . . . . -
4096
Needed =
4004
DIP switch 12 . . . . . -
2048
Needed =
1956
DIP switch 11 . . . . . -
1024
Needed =
932
DIP switch 10 . . . . . -
512
Needed =
420
DIP switch 9 . . . . . -
256
Needed =
164
DIP switch 8 . . . . . -
128
Needed =
36
DIP switch 6 . . . . . -
32
Needed =
4
DIP switch 3 . . . . . -
4
Therefore, DIP switches 3, 6, 8, 9, 10, 11, 12, and 13 would be set to “ON”.
Note: If the desired reading is 18.0, the SM can be set for a value of 10. (To get
the D.P. required, the unit must be powered down, then switches 7 and 8 set
appropriately, then powered back up.)
EXAMPLE 2 (for APLPT5):
DESIRED READING = 2 hours and 23 minutes (2-23)
PULSES PER SECOND = 230 pulses per second
First convert the D.R. to its base units.
D.R. = 2 (hours) x 60 + 23
DMIT = 143 x 230 PPS
= 120 + 23
= 32,890
= 143
DMIT = 32,890 ÷ 10
*
DMIT = 3,289
*
Since the required DMIT does exceed 16,383, a value of 10 is used for the S.M.
DMIT = 3289
DIP switch 12 . . . . . -
2048
Needed =
1241
DIP switch 11 . . . . . -
1024
Needed =
217
DIP switch 8 . . . . . -
128
Needed =
89
DIP switch 7 . . . . . -
64
Needed =
25
DIP switch 5 . . . . . -
16
Needed =
9
DIP switch 4 . . . . . -
8
Needed =
1
DIP switch 1 . . . . . -
1
Therefore, DIP switches 1, 4, 5, 7, 8, 11, and 12 would be set to “ON” for a
display of 2-23. DIP switch 4 on the side panel must be set to “ON” to obtain
the S.M. value of 10.