Vogt P18AL TUBE-ICE, Руководство по обслуживанию

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P18AL Service Manual
INSTALLING YOUR TUBE-ICE
®
MACHINE
3/6/07
3-10
Phase Check
! CAUTION !
DO NOT attempt to start machine without priming pump
and insuring proper rotation of both cutter and pump.
! CAUTION !
Cutter and pump motor rotation are factory synchronized but
must be checked at installation. For
ice production, the cutter disc, as viewed at the ice discharge opening should turn from left to right
(crushed rotation should be from right to left). The pump rotation should match the marking on the
pump housing. The pump will need to be primed by starting the machine in the clean mode and
allowing it to run for several minutes. To change direction of rotation for both, cutter and pump,
disconnect power and reverse L1 and L3 (incoming power wires) at the compressor motor contactor.
Voltage Unbalance
Voltage unbalance can cause motors to overheat and fail.
The maximum voltage unbalance between any two legs should be no greater than 2%.
Example: Supply Voltage = 230-3-60
Voltage Readings: AB = 220 Volts
BC = 225 Volts Average = (220 + 225 + 227)/3 = 224 Volts
AC = 227 Volts
(AB) 224-220 = 4 Volts (Highest Deviation)
(BC) 225-224 = 1 Volts
% Voltage Unbalance = 100 x (4/224) = 1.78% “Acceptable”
(AC) 227-224 = 3 Volts
Important: If the supply voltage phase unbalance is more the 2%, contact your local
electric utility company.
Current Unbalance
Voltage unbalance will cause a current unbalance, but a current unbalance
does not necessarily mean that a voltage unbalance exists. A loose terminal connection or a buildup
of dirt or carbon on one set of contacts would cause a higher resistance on that leg than on the other
two legs. Current follows the path of least resistance, therefore if terminal connection L1 is loose or
dirty, L2 and/or L3 will have higher current. Higher current causes more heat to be generated in the
motor windings.
The maximum acceptable current unbalance is 10%.
Example:
Current Readings: L1 = 96 Amps
L2 = 91 Amps Average = (96 + 91 + 98)/3 = 95Amps
L3 = 98 Amps
(L1) 96-95 = 1 Amps
(L2) 95-91 = 4 Amps (Highest Deviation) % Current Unbalance = 100 x (4/95) = 4.2% “Acceptable”
(L3) 98-95 = 3 Amps