Name _______________        School ____________

Fall Clinic – 2006

 

Energy Systems Skill

 

You are the manager of a grain elevator and after a recent expansion you need to install electric motors and the correct size pulley.  Your augers came with a twelve-inch pulley attached to the shaft.  After reading your installation instructions you realize that the desired speed for your grain auger is 300 rpm.  Your electric motors have just arrived by truck. You need to get the necessary information from the motor nameplate to be ready to install the new motors.  You want to use the highest voltage available for the motor so that the electric wire can be the smaller size.

 

The desired speed for your auger is 300 rpm, and your augers have all been installed with a 12-inch pulley.  Using the rpm listed on the motor, determine the size pulley required to set the augers on a 300 rpm speed.

 

Motor nameplate information:

 

1.  Higher voltage: _________

 

2.  Amperage requirement: __________

 

3.  Motor rpm: ____________

 

4.  Using the following formula, what size pulley should be selected for the motor?  _______

 

            Motor speed X pulley size = machine speed X pulley size

 

 

 

 

 

 

 

 

 

 

 

5.  Given the two types of pulleys used, what size of v-belt should be selected?  Circle one. (Hint: measure pulley width and select belt from the chart on next page; agricultural belts have the ÒHÓ in front of the belt size.)

 

            HA      HB      HC      HD      HE

 

 

6.  If the motor requires overload protection (circuit breaker or fuse) that is 125 percent of rated amperage, what size overload protection is required for each motor?  ___________

 

7.  If the motors are wired for the lower voltage, how do you change the wiring for the higher voltage?  __________________________________________________________

________________________________________________________________________

 

8.  If the motors are rotating the wrong way, how do you change the rotation? ___________

________________________________________________________________________

________________________________________________________________________

 

Evaluation:

                                                                                    Points Possible            Earned

            1.  nameplate information                                            3

            2.  Calculations and pulley selected                             12

            3.  V-belt size                                                              5

            3.  Changing voltage                                                   5

            4.  Changing rotation                                                   5_____            ______

                                                            Total                            30