Determining Metering Rate
To insure accuracy a METERING RATE must be determined for each color. It is only necessary to determine Metering Rate once for each color. Record Metering Rate for each color for future reference.
- Switch to CYCLE.
- Turn CALIBRATION knob (upper right corner) to "CALIBRATE".
This will force one cycle of 100 counts to be dispensed.
OR: Set counter to 100 and switch from OFF to CYCLE.
Plug in SIGNAL cord to force cycle of 100 counts.
- Run several cycles and record GRAM WEIGHT metered each cycle.
The average of these weights is the METERING RATE in grams/100ct.
Example: Each CALIBRATION cycle produces 55 grams output.
Your METERING RATE is 55 grams/100ct.
MPA Liquid Color Pump - Formulas for setting the counter
INJECTION MOLDING (Cycle Mode):
- Determine the WEIGHT of the entire shot IN GRAMS.
- Determine the LBS. of COLOR per 100 LBS. of natural required, (or KILOS of COLOR per 100 KILOS of natural).
- Determine the METERING RATE for each color in grams/100 counts.
- Set the digital counter using the following formula:
(Shot wt) x (lbs/100) / (grams/100ct) = Setting
Use this Calculator to do the math for you. Fill in the fields in the green area then click Calculate.
Note: calculator rounds to the nearest 10th
EXTRUSION (Continuous Mode):
- Determine the extruder output in pounds per hour.
- Determine the LBS. of COLOR per 100 LBS. of natural required, (or KILOS of COLOR per 100 KILOS of natural).
- Determine the METERING RATE in grams/100 counts.
- Set the digital counter using the following formula:
(lbs/hr) x (lbs/100) / (grams/100ct) x .71 = Setting
Use this Calculator to do the math for you. Fill in the fields in the green area then click Calculate.
Note: calculator rounds to the nearest whole number.
ALTERNATE FORMULA METHOD
This method does not require calibration, but instead relies on an accurate knowledge of the weight of the liquid (lbs/gal) and accurate tube sizes.
INJECTION MOLDING (Cycle Mode):
- Determine the WEIGHT of the entire shot in GRAMS.
- Determine the PERCENT color let-down desired.
- Determine the weight of the liquid color in POUNDS per GALLON. or GRAMS per LITER (G/L).
- Set the digital counter using the following formula:
(Shot Weight) x (% let-down) x ('C' factor) / (lbs/gal) = Setting
or (Shot Weight) x (% let-down) x ('C' factor) x 120 / (G/L) = Setting
Use this Calculator to do the math for you. Fill in the fields in the green area then click Calculate.
Note: calculator rounds to the nearest 10th.
EXTRUSION (Continuous Mode):
- Determine the extruder output in pounds per hour.
- Determine the percent color let-down desired.
- Determine the weight of the liquid color in pounds per gallon or GRAMS per LITER (G/L).
- Set the digital counter using the following formula:
(lbs/hr) x (% let-down) x ('E' factor) / (lbs/gal) = Setting (Use top Calculator)
or (lbs/hr) x (% let-down) x ('E' factor) x 120 / (G/L) = Setting (Use bottom Calculator)
Use this Calculator to do the math for you. Fill in the fields in the green area then click Calculate.
Note: calculator rounds to the nearest whole number.
Tube Size |
'C' factor |
'E' factor |
1/8" I.D. (green) |
1.3 |
.93 |
3/16" I.D. (red) |
.66 |
.47 |
1/4" I.D. (clear) |
.39 |
.28 |
NOTE: If you have Model MPA-6-18 (which uses an 18 RPM motor) then multiply these factors by six, i.e. (6 x C factor).