APPLICATION NOTE NO. 40

SBE 5T Pump Speed Adjustment Instructions
Revised May 2005

Application note in pdf format

Equipment: DC power supply , Frequency Counter
Drawings (below): 31441B (schematic), 41250A (assembly)

The pump housing must be disassembled to adjust the pump speed. Referencing above drawings:

1. Remove the white plastic end cap retainer ring located at the connector end of the pump by twisting in a counter-clockwise motion.

2. Install a 2-pin dummy plug with locking sleeve over the bulkhead connector to provide a good grip on the pump connector and protect the connector pins. Rotate the connector back and forth while carefully pulling the end cap away from the housing. Pull the end cap (piston o-ring seal) out of the housing. The motor and electronics assembly are attached to the end cap and will come out as a unit.

3. Connect the positive lead of your frequency counter to the yellow test post (T1) (drawing 41250A). Connect the frequency counter ground (negative) to the power supply ground (negative).

4. Supply power:

• Low voltage pump (pump with LV in the serial number) -- Supply 6 volts DC power to the bulkhead connector (large pin is common, small pin is positive) or directly to the PCB (P8 is positive, P19 or P18 is common, drawing 41250A.)
• Normal voltage pump -- Supply 12 volts to the bulkhead connector (large pin is common, small pin is positive) or connect directly to the PCB (P8 is positive, P19 or P18 is common, drawing 41250A.)

5. A 2K ohm potentiometer (R11, drawing 41250A) is located on the back side of the board. Adjust the potentiometer to obtain the frequency corresponding to the desired speed (Frequency * 30 = rpm).

• Pittman 18.2 ohm motor (P/N 3711B113-R1) -- Set jumper position P15 to P17 (1300 rpm) and P12 to P13 (1300 rpm) and adjust the speed as desired, up to the nominal maximum of 2000 rpm.
• Pittman 7.4 ohm motor (P/N 3711B112-R1) -- Set jumper position P15 to P16 (3000 rpm) and P14 to P13 (3000 rpm) and adjust the speed as desired, up to the nominal maximum of 4500 rpm. To adjust speed below approximately 2200 rpm, set the jumper position P15 to P17 (1300 rpm) and P12 to P13 (1300 rpm), and adjust speed using the potentiometer.
• Pittman 3.55 ohm motor (P/N 3711B112-R2) -- Set jumper position P15 to P16 (3000 rpm) and P14 to P13 (3000 rpm) and adjust the speed as desired, up to the nominal maximum of 4500 rpm. To adjust speed below approximately 2200 rpm, set the jumper position P15 to P17 (1300 rpm) and P12 to P13 (1300 rpm), and adjust speed using the potentiometer.

6. Disconnect the frequency counter and the power supply. Make sure the O-ring and mating surfaces are clean. Lightly lubricate the o-ring before inserting the connector end cap into the housing. Replace the pump end cap retainer.

View Adobe Acrobat .pdf drawings:

Drawing 31441B (schematic)

Drawing 41250A (assembly)

Last modified: 06-Apr-2007

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