Teral NSVM 25 Series, Installation & Operating Manual

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NSVM, NSVMN
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WARNING
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If it is necessary to increase the diameter of the suction pipe, place an eccentric reducer
between the check valve and the flexible pipe section.
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Using elbows will increase the flow resistance. Wide bends will result in lesser flow resistance.
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The piping must have a level or positive gradient to prevent the formation of air pockets.
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The diameter of the drop pipe must be bigger than the diameter of the pump’s suction port.
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Use a foot valve in case of negative suction head.
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Size pump for correct head.
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Place the intake of the suction pipe so that the intake is always submerged to prevent entry of air.
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Install a compound gauge at the pump suction and a pressure gauge at the pump discharge.
6. Electrical connection
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All electrical connection should be in accordance with the local regulations and made by a qualified electrician.
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Make sure that the supply voltages and frequencies, and phase are suitable for the motor used.
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Before proceeding, make sure that all the connections are grounded and well insulated.
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Overload protection should be provided.
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To connect, proceed as shown on the inside of the terminal board cover.
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The terminal box can be turned to four positions.
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Check the direction of rotation (Three-phase motor only).
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Make sure that the controls are properly grounded.
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To avoid the possibility of dry running, we strongly recommend installing dry running protection.
7. Start-up
The pump and suction pipe should be filled with the liquid to be pumped before start-up to prevent dry running at start-up.
Dry running can damage the pump bearing and shaft seal.
7.1 Operation
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Start the pump and check the direction of rotation of the motor (Three –Phase motors).
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Start the pump, keeping the on-off valve of the discharge side of the pump closed. Then, open the on-off valve slowly. The
pump must run smoothly and noiselessly. If not, then it may be necessary re-prime the pump.
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Check the current drawn of the motor. If necessary, adjust the setting of the thermal relay.
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Any air pockets trapped inside the pump may be released by adjusting the air screw.
If the pump is installed in a location where it is subject to freezing when not in operation, then the pump
and the pipe system
should be drained to prevent damage from freezing.
WARNING