Crane Barnes SGV 2 HP, Руководство по обслуживанию

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SGV 2HP Disassembly
Visual Inspection of Pump
Quick visual inspections can save time. A visual Examination of the pump for damage to cords, controls, or
cutter, and a thorough electrical check should be performed to determine a pumps condition.
Cut Cords
Check the cord(s) for any cuts or gouges. If there is any noticeable damage, do not use the cord, remove,
and install a new cord if applicable.
Megger the Pump Leads - (Megohmmeter)
This test is to determine the strength resistance of the cord insulation. The meter will test zero Ω if the cord
insulation is damaged or breaking down thus allowing current to fl ow through the insulation.
This test can best be performed if the pump leads are disconnected from the control panel, or the junction
box. To perform this test, touch one lead to the green ground. Touch the other lead to the red wire. Repeat
this test with ground to black and ground to white. To pass this test, a cord set must have a reading of 5mΩ
or higher on all leads. Note that a “0” reading indicates a dead short.
CAUTION: After performing a megger test ALWAYS discharge cord set leads to ground.
Hi-Pot (High Potential) Insulator Test (if required)
A Hi-Pot test of pump leads is more accurate than a megger test, either method will indicate the condition
of cord insulation. In most cases, it is not necessary to do both.
This test detects non-visible insulator failures. To perform the HiPot test, a 500 VOC Megohmmeter is
needed. Touch the green ground lead from the pump to one of the meter leads, and the other meter lead
to one of the power leads. Repeat this test with all of the power leads. A resistance reading no less than
20mΩ
IS ACCEPTABLE.
CAUTION: After performing a Hi-Pot test, ALWAYS discharge cord set leads to ground.
Check the Resistance - (Multi-Meter)
CAUTION: Perform this test with the pump off.
This test is to check for open circuits or loose connections and also to determine if the motor windings are
good.
To perform this test, touch one meter lead to the red pump lead, touch the other meter lead to the black
pump lead, record the reading. Then compare the readings to the readings found on motor winding
resistance charts (Table 1). Readings should be within ±5% of nameplate.