2000 Autoflow
ELECTRICAL POWER SUPPLY
Power Supply
An adequate power supply and proper wiring are impor- tant factors for maximum performance and long life of the dryer. Electrical service must be adequate enough to prevent low voltage damage to motors and control cir- cuits (see Electrical Load Information on page 40). In
220V 1 ph and 220V 3 ph systems a separate neutral wire is required for the 120V heater circuit, and should be connected to terminal #1 in the master heater. Do not run in conduit with motor power lines.
Transformer and Wiring Voltage Drop
It is necessary to know the distance from the unit to the available transformer, and the horsepower of your fan unit. Advise the service representative of your local power supplier that an additional load will be placed on the line. Each fan motor should be wired through a fused or cir- cuit breaker disconnect switch. Check on KVA rating of transformers, considering total horsepower load. The power supply wiring, main switch equipment and trans- formers must provide adequate motor starting and oper- ating voltage. Voltage drop during motor starting should not exceed 14% of normal voltage, and after motor is running at full speed it should be within 8% of normal voltage. Check Electrical Load Information for HP rat- ings and maximum amp loads to properly size wire and fusing elements. Standard electrical safety practices and codes should be used. (Refer to National Electrical Code Standard Handbook by National Fire Protection Asso- ciation).
Machine to Earth Grounding
It is very important that a Machine To Earth Ground Rod be installed at the fan. This is true even if there is a ground at the pole 15 feet away. Place the ground rod that comes standard, within 8 feet of the dryer and attach it to the dryer control panel with at least a #6 solid, bare, copper ground wire and the clamp pro- vided. The grounding rod located at the power pole will not provide adequate grounding for the dryer. The proper grounding will provide additional safety in case of any short and will ensure long life of all circuit
boards, and the ignition system. The ground rod must
be in accordance with local requirements.
Proper Installation of Ground Rod
It is not recommended that the rod be driven into dry ground.
Follow these instructions for proper installation:
1.Dig a hole large enough to hold 1 to 2 gallons of water.
2.Fill hole with water.
3.Insert rod through water and jab it into the ground.
4.Continue jabbing the rod up and down. The water will work its way down the hole, mak- ing it possible to work the rod completely into
the ground. This method of installing the rod gives a good conductive bond with the surrounding soil.
5. Connect the bare, copper ground wire to the rod with the proper ground rod clamp. See Figure 12.
6.Connect the bare copper ground wire to the fan control boxes with a grounding lug.
7.Ground wire must not have any breaks or splices.
Dig a hole large enough to hold 1 or 2 gallons of water. Work the ground rod into the earth until it is completely in the ground.
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