Vogt P-34AL-15, Руководство по обслуживанию

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P34AL-15 & P34ALOF-15 Service Manual
INSTALLING YOUR TUBE-ICE MACHINE
9/22/05
3-13
Voltage Unbalance Voltage unbalance can cause motors to overheat and fail. Voltage imbalance
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
(AC) 227-224 = 3 Volts
% Voltage Unbalance = 100 x (4/224) = 1.78% “Acceptable”
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)
(L3) 98-95 = 3 Amps
% Current Unbalance = 100 x (4/95) = 4.2% “Acceptable”
Rotation Check.
The cutter and pump motor rotation are factory synchronized, but must be
checked at installation. For cylinder ice production, the cutter disc as viewed at the ice discharge
opening should turn from left to right.
Check rotation by the following procedure:
1. Turn the power to the machine on and check voltages.
2. Make sure the water tank is full of clean water.
3. Turn the Hand-Auto switch (ISS) to HAND position. The water pump will start and the freezing
(1LT) and the liquid feed (2LT) pilot lights will illuminate. Check pump rotation.
4. Push the MANUAL HARVEST button. The water pump will stop, the “Freezing and Liquid
Feed” lights will go out, and after 20-30 seconds, the cutter motor will start. The thawing gas
solenoid valve will open and the “Thawing” pilot light (3LT) will illuminate.