Electrical power supply – Grain Systems PNEG-897 User Manual

Page 8

1999 Top Dry Wiring Diagrams

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).

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).

Transformer and Wiring Voltage Drop

Proper Installation of Ground Rod

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,

Machine to Earth Grounding

It is not recommended that the rod be driven into dry

ground.

Follow these instructions for proper installation:

Dig a hole large enough to hold 1 to 2 gallons

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 wa

ter will work its way down the hole, making

it possible to work the rod completely into

the ground. This method of installing the

rod gives a good conductive bond with the sur

rounding soil.

5. Connect the bare, copper ground wire to

the

rod with the proper ground rod

clamp. See

Figure 8.

6. Connect the bare copper ground wire to the fan

control boxes with a grounding lug.

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.

ELECTRICAL POWER SUPPLY

and the ignition system. The ground rod must be in

accordance with local requirements.

7. Ground wire must

not have any breaks

or splices.