BE 3rd trimester day 6 test

Actuator position feedback is: 

• Used in floating controls  

• Used in proportional control  

• A stray voltage or current in a control circuit  

As compared to across the line starters, reduced voltage starters: 

• Reduce starting torque required  

• Reduce inertia loads  

• Reduce starting current inrush   

A dual element fuse has: 

• Two normal one-time fuse links  

• A thermal cut out only  

• A thermal cut out in a normal fuse link 

An expected advantage of an electronic control system as compared to any other type of system would be: 

• Is less expensive

• Has greater sensitivity  

• No need for an external power source 

For ease of starting, a centrifugal refrigeration machine should be started with: 

• Cylinders unloaded  

• Inlet vanes closed  

• Inlet vanes open  

The purpose of a dual input motor field coil in a two-wire spring return actuator is to: 

• Reverse the actuator movement when the thermostat call for heat 

• Eliminate the need for actuator limit switches 

• Reduce power input at the end of the power stroke  

For successful application of floating controls , there must be: 

• Very little time lag  

• Considerable time lag  

• An anticipator in the thermostat  

The control point of a thermostat is:  

• The same as the set point  

• 1/2 the differential  

• The temperature that the thermostat operates to maintain  

Line or ladder type electrical diagrams are most useful for: 

• Doing the actual wiring  

• Showing the color coding of the wiring  

• Understanding circuit operation 

A self-contained automatic control system requires: 

• Compressed air 

• Electric power 

• No external power