MEP
True or False, K2 Cranking Relay is located in the DSC control box
False
The Alaskan ECU requires __ __, __ Hertz, __ phase for operation.
208 VAC, 60 HZ, 3 Phase
What component in the Alaskan ECU protects the heater circuit?
CB2 Protects the heater circuit
What is the De-Minimus when referring to a refrigeration system?
The minimum amount of refrigerant able to be released into the atmosphere when working with refrigerant systems.
How does a Multi-Meter show a difference in potential?
By subtracting the difference of the readings on both end of the multi-meter.
Explain how the Ether Circuit operates?
During extreme cold weather operations user will close S9 (Ether Switch) while starting up engine
When will condenser fan 1 & 2 open and close in our Alaskan ECU?
Condenser Fan #1 will open @ 170 PSI and close @ 250 PSI
Condenser Fan #2 will open @ 210 PSI and close @ 320 PSI
What component in the Alaskan ECU is used to protect the Mode Selector Switch?
CB1 Protects the Mode Selector Switch
Explain the three different types of heat transfer methods
Conduction, Convection and Radiation.
What steps must be taken when performing a resistance check on a component?
Remove Power, Isolate one end of the component.
What are the two functions of the Fault Reset Switch?
To bypass any faults, and to send 24V VDC to governor controller to switch from no fuel to fuel position
What would be the underlining issue if there was a dirty condenser coil, Condenser fan #2 in-op and the hot gas bypass valve stuck open?
The High Pressure Cut-out switch keeps tripping
What is the primary function of VE3 and explain how it works.
VE3 prevents excessive compressor discharge temperature
What are the three heat types?
Sensible heat, latent heat and superheat
How many degrees separate the three different AC phases?
120 Degrees
Explain in detail how we use the auxiliary fuel pump system.
While connected to and auxiliary fuel source the user must flip S1 (Master Switch) back one position to the Auxiliary fuel mode thus allowing the unit to transfer fuel from the fuel source.
Explain how VE1 maintains its superheat?
Temperature is sensed by the sensing bulb working along with the spring tension and the evaporator pressure.
Bulb Pressure (P1) = Spring Tension (P3) + Evaporator Pressure (P2)
What would happen if we flipped the battle short switch during normal operation?
All circuits would be bypassed except Overspeed Short Circuit
Explain how pressure and boiling point correlate in our system.
As system pressure rises so does boiling point.
What reading will be displayed when connecting a multi-meter lead to an energized relay on the power side and the neutral side?
120 VAC
Explain the relationships between the Power Potential Transformer and the Voltage Regulator in its entirety .
The Power Potential Transformer provides a 29 VAC for sensing and 160 VAC for operating. Once this voltage has been provided to the voltage regulator it may now continuously flash the field.
What are the three characteristics of the hot gas bypass valve VH1?
Factory set from 45 - 48 PSIG, Adjustable, Helps prevent low suction pressure
Explain the relationship between the CIM, Backplane and I/O
When there is adjustment made via the control panel, the CIM will receive the information that is manually being inserted by the user and send a digital signal to the IO. The IO will then translate the data signal into an analog signal which will be sent to the backplane. The exchange of data will constantly be back and forth between the three systems.
How do we determine the maximum weight of our refrigeration bottles?
Tare Weight + Safe Fill Weight = Max Weight
Explain the difference between AC and DC electrical system.
AC is alternating current with forward and backwards flow, DC is direct with only forward flowing current.