EBARA DSC4 - Manual (Page 10)

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INSTRUCTION MANUAL Model DSC4
3.6.2 Insulation Resistance Measurement
WARNING: ALL ELECTRIC WORK SHOULD BE PERFORMED BY A QUALIFIED
ELECTRICIAN AND ALL NATIONAL AND LOCAL ELECTRICAL CODES MUST BE OBSERVED.
Although insulation resistance of this pump has been shop tested, it should be rechecked prior
to installation, using the following procedure. Usually, insulation resistance of a minimum of
50MW is considered satisfactory (when measured with a DC 500V Megger).
Measurement procedure (Refer to Figs. 10 and 11)
Connect the minus (-) terminal to G of the DC 500V Megger to the G terminal of the power
cable, or a motor bolt.
Touch the plus (+) terminal of the Megger to L1-phase (or L2-phase or L3-phase) of the power
cable, and read the insulation resistance.
Touch the plus (+) terminal of the Megger to P1 (or P2) and P3 (or P4) of the protective device
cable, with the minus (-) terminal G connected as above, and read the insulation resistance.
CAUTION: DO NOT CONNECT THE TWO MEGGER TERMINALS BETWEEN P1 AND P2
OR P3 AND P4, TO AVOIDDAMAGE TO THE PROTECTIVE DEVICE.
KEEP THE CABLES OFF THE GROUND WHILE TAKING ALL MEASUREMENTS.
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INSTRUCTION MANUAL Model DSC4
Fig. 20
(3) Mechanical Seal (lower)
(a) Unplug the “oil drain” and “air vent” and drain all internal oil. (Refer to “Changing Oil”,
Para 6.6).
(b) If the drained oil is muddy, or milky-white, it contains water.
The mechanical seal (lower) is in satisfactory condition as long as the oil does not contain
much water. Otherwise, it must be replaced.
(c) After the oil has been inspected, pour fresh oil (Turbine Oil ISO VG32) through the
“oil port”, with the pump in a vertical position, till oil overfl ows from the “air vent”. The
quantity of oil is shown in Table 1.
(d) Replug the “oil port” as carefully as the other ports.
(e) To replace either upper or lower mechanical seal, the pump must be disassembled.
As the mechanical seal is a cartridge type, removing the retaining ring permits seal
removal as a complete assembly. After the mechanical seal has been replaced with a
new one, reassemble the pump and supply the specifi ed oil through the “oil port” in the
manner describe above. At this point, turn the rotating body by hand to ensure that it
turns smoothly.
Also, check for oil leaks.
Check hole
plug
Oil port plug
Air vent hole
plug
Oil drain
plug
Mechanical seal