Added capacitors must be connected across “Red” and “Black” control box terminals, in parallel with any existing running capacitors. The additional capacitor(s) should be mounted in an auxiliary box. The values of additional running capacitors most likely to reduce noise are given below. The tabulation gives the max. S.F. amps normally in each lead with the added capacitor.
Although motor amps decrease when auxiliary run capacitance is added, the load on the motor does not. If a motor is overloaded with normal capacitance, it will still be overloaded with auxiliary run capacitance, even though motor amps may be within nameplate values.
MOTOR RATING | NORMAL RUNNING CAPACITOR(S) | AUXILIARY RUNNING CAPACITORS FOR NOISE REDUCTION | MAXIMUM AMPS WITH RUN CAMP | |||||
HP | VOLTS | MFD | MFD | MIN. VOLTS | FRANKLIN PART | YELLOW | BLACK | RED |
1/2 | 115 | 0 | 60(1) | 370 | TWO 155327101 | 8.4 | 7 | 4 |
1/2 | 230 | 0 | 15(1) | 370 | ONE 155328101 | 4.2 | 3.5 | 2 |
3/4 | 0 | 20(1) | 370 | ONE 155328103 | 5.8 | 5 | 2.5 | |
1 | 0 | 25(1) | 370 | ONE EA. 155328101 155328102 | 7.1 | 5.6 | 3.4 | |
1.5 | 10 | 20 | 370 | ONE 155328103 | 9.3 | 7.5 | 4.4 | |
2 | 20 | 10 | 370 | ONE 155328102 | 11.2 | 9.2 | 3.8 | |
3 | 45 | None | 370 | 17 | 12.6 | 6 | ||
5 | 80 | None | 370 | 27.5 | 19.1 | 10.8 | ||
7.5 | 45 | 45 | 370 | ONE EA. 155327101 155328101 | 37 | 32 | 11.3 | |
10 | 70 | 30 | 370 | ONE 155327101 | 49 | 42 | 13 | |
15 | 135 | NONE | 75 | 62.5 | 16.9 |
When the available power supply voltage is not within the proper range, a buck-boost transformer is often used to adjust voltage to match the motor. The most common usage on submersible motors is boosting a 208 volt supply to use a standard 230 volt single-phase submersible motor and control. While tables to give a wide range of voltage boost or buck are published by transformer manufacturers, the following table shows Franklin’s recommendations. The table, based on boosting the voltage 10%, shows the minimum rated transformer kVA needed and the common standard transformer kVA.
MOTOR HP | 1/3 | 1/2 | 3/4 | 1 | 1.5 | 2 | 3 | 5 | 7.5 | 10 | 15 |
LOAD KVA | 1.02 | 1.36 | 1.84 | 2.21 | 2.65 | 3.04 | 3.91 | 6.33 | 9.66 | 11.7 | 16.6 |
MINIMUM XFMR KVA | 0.11 | 0.14 | 0.19 | 0.22 | 0.27 | 0.31 | 0.4 | 0.64 | 0.97 | 1.2 | 1.7 |
STANDARD XFMR KVA | 0.25 | 0.25 | 0.25 | 0.25 | 0.5 | 0.5 | 0.5 | 0.75 | 1 | 1.5 | 2 |