Grain Systems PNEG-1891 - Manual (Page 43)

7
Power Supply
Topics Covered in this Chapter
▪ Guidelines for Supplying Adequate Power
▪ Installing the Machine-to-Earth Grounding Rod
▪ Guidelines for Powering Auxiliary Conveyors
▪ Specifications for the Electrical Load on a Portable Dryer
Guidelines for Supplying Adequate Power
An adequate power supply and proper wiring are important factors for ensuring maximum performance
and long life of the dryer.
• Ensure that electrical service is adequate to prevent low-voltage damage to motors and control cir-
cuits. Refer to Specifications for the Electrical Load on a Portable Dryer, page 45 for power supply
requirements.
• Power supply for single-phase models must include a neutral wire.
WARNING
All dryers are equipped with a main electrical disconnect switch on the main
control box. This switch turns off the main power to the dryer. Make sure to turn
off the main electrical disconnect switch before inspecting or servicing the
dryer.
• Advise the service representative of the local power supplier that an additional load will be placed on
the line.
• Considering the total horsepower load, check the KVA rating of transformers.
• The voltage drop during a motor start must not exceed 14% of the normal voltage. The power supply
wiring, main switch equipment, and transformers must provide adequate motor startup and operating
voltage.
• Verify that the motor is within 8% of the normal voltage when it is operating at full speed.
• Check the electrical load information for HP ratings and the maximum amp loads.
Installing the Machine-to-Earth Grounding Rod
To help protect circuit boards, the variable frequency drive (VFD), and the ignition system if electrical short
circuits occur, you must install a machine-to-earth grounding rod.
What You Should Know
The machine-to-earth grounding rod that is located at the power pole does not provide adequate grounding
for the dryer. The grounding rod that you install must be in accordance with local requirements.
Pneg-1891 Portable Dryers 43