Franklin 2007 manual Preliminary Tests All Sizes Single- and Three-Phase, Resistance

Maintenance – All Motors

Table 44 Preliminary Tests - All Sizes Single- and Three-Phase

“TEST”

PROCEDURE

WHAT IT MEANS

	1.	Open master breaker and disconnect all leads from control	1.	If the ohms value is normal (table 45), the motor is
		box or pressure switch (QD type control, remove lid) to		not grounded and the cable insulation is not damaged.
		avoid electric shock hazard and damage to the meter.
			2.	If the ohms value is below normal, either the windings
Insulation	2.	Use a megohmmeter or set the scale lever to R X 100K		are grounded or the cable insulation is damaged.
		on an Ohmmeter. Zero the meter.		Check the cable at the well seal as the insulation is
Resistance
				sometimes damaged by being pinched.
	3.	Connect one meter lead to any one of the motor leads
		and the other lead to the metal drop pipe. If the drop pipe is
		plastic, connect the meter lead to ground.
	1.	Open master breaker and disconnect all leads from control	1.	If all ohms values are normal (tables 13, 22, 24 & 26), the
		box or pressure switch (QD type control, remove lid) to		motor windings are neither shorted nor open, and the
		avoid electric shock hazard and damage to the meter.		cable colors are correct
	2.	Set the scale lever to R X 1 for values under 10 ohms.	2.	If any one value is less than normal, the motor
		For values over 10 ohms, set the scale lever to R X 10.		is shorted.
Winding		“Zero” the Ohmmeter.
			3.	If any one ohm value is greater than normal, the
Resistance	3.	On 3-wire motors measure the resistance of yellow to black		winding or the cable is open, or there is a poor cable
		(Main winding) and yellow to red (Start winding).		joint or connection.
		On 2-wire motors: measure the resistance from line-to-line.	4.	If some ohms values are greater than normal and some
				less on single-phase motors, the leads are mixed. See
		Three-phase motors: measure the resistance line-to-line		page 46 to verify cable colors.
		for all three combinations.

				ATTACH THIS LEAD
				TO WELL CASING OR
				DISCHARGE PIPE
	L1 L2 R	Y B		CONNECT		L1 L2 R	Y B
				THIS LEAD
				TO GROUND
		RED					RED
		YELLOW					YELLOW
		BLACK					BLACK
TO	GROUND				TO	GROUND
POWER	L1	BLACK			POWER	L1
SUPPLY {	L2	YELLOW		TO	SUPPLY {	L2	BLACK		TO
							YELLOW
		RED	PUMP					PUMP
			{				RED
		GROUND						{
POWER MUST					POWER MUST		GROUND
BE SHUT OFF
					BE SHUT OFF
		MEGGER					OHMMETER
		OR OHMMETER
							SET AT R X 1
		SET AT R X 100K
	FIG. 13					FIG. 14

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