JBT FoodTech Frigoscandia GYRoCOMPACT M7, Руководство по установке

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DOCUMENT NUMBER: 204-01GB-00 PAGE: 1/2
EQUIPMENT: GC
SERVICE INFO NUMBER: 204
REVISION DATE: FEBRUARY, 1999
REVISED BY: JKA
SERVICE INFORMATION
FAN DRIVEN BY-PASS AIR
BALANCE TUNNEL
1. Function
The air balance tunnel creates air curtains
preventing air from blowing out or in through the
openings. The air curtains also prevents the
products from moving while they are inside the
tunnel.
The air flow in the tunnel is created by a fan
which is controlled by a frequency converter. The
rotation speed of the motor can be adjusted from
the control panel.
2. Adjustment
First check the rotation direction of the fan wheel
(illustration 2a).
Use plastic strips attached over the outfeed
according to illustration 2b to find out if you have
an air flow through the infeed or outfeed.
Adjust the fan until there is no air flow through
the opening.
Note: Final test must be made during production
with cold freezer and with product.
If no product is available, a pressure drop can be
achieved by loading plastic sheets on some belt
tiers.
3. Ramp down time
Set a ramp down time at the frequency converter
to avoid over current when the fan motor speed
is reduced quickly:
1. Run the fan motor at its highest speed.
2. Stop the motor.
3. Measure the time until the fan wheel stops
rotating.
4. Set the ramp down time to the measured
value (see Service-Info about adjustment of
frequency converter).
Note: When adjusting the fan rotation speed
downwards you have to wait a few seconds
before the new speed is reached.
1a: Air balance tunnel.
2b: Plastic strips attached over the infeed
or outfeed.
1b: Air flow in the tunnel.
Air flow in stack,
downwards
Air flow in stack,
upwards
2a: Rotation direction of the fan wheel.