Skills and Trades

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Variable frequency drives (VFD) reduce the speed of AC motors by: A) Controlling the frequency ... Started by codyclark	3 Replies 71 Views	Jul 26, 2018 by javimendoza7
The start capacitor is removed from the compressor circuit by: A) A potential starting relay. B) ... Started by lak	1 Replies 70 Views	Jul 26, 2018 by taylorsonier
The fastest method for charging a large system which holds 50 pounds of refrigerant is to add: A) ... Started by DelorasTo	1 Replies 47 Views	Jul 26, 2018 by mirabriestensky
The capacity of a capacitor can be tested: A) By checking the residual current draw of the ... Started by KWilfred	1 Replies 26 Views	Jul 26, 2018 by Jane
By having a capacitor in series with the start winding of an induction motor: A) The start ... Started by cherise1989	3 Replies 80 Views	Jul 26, 2018 by efwsefaw
Systems with fixed restriction metering devices are critical to charge because: A) They can only ... Started by jilianpiloj	1 Replies 64 Views	Jul 26, 2018 by jonathanballen97
The most common type of single phase motor used in HVACR equipment is: A) Repulsion start ... Started by kamilo84	1 Replies 16 Views	Jul 26, 2018 by dawsa925
A fixed restriction system operating with a refrigerant undercharge will have: A) A high system ... Started by fahad	1 Replies 36 Views	Jul 26, 2018 by rnehls
An air conditioning system charged with R-410A is operating with a suction pressure of 130 psig ... Started by NClaborn	3 Replies 83 Views	Jul 26, 2018 by bbburns21
ECM motor speed is controlled by: A) The frequency and the number of poles. B) The voltage ... Started by 123654777	1 Replies 53 Views	Jul 26, 2018 by bbburns21
More charge should be added if: A) The system subcooling is exactly the same as specified. B) ... Started by lak	1 Replies 18 Views	Jul 26, 2018 by princessflame2016
A technician has installed a new 3 phase motor but it is running in reverse. What should she do to ... Started by pepyto	1 Replies 102 Views	Jul 26, 2018 by Silverbeard98
Isolation joints are also known as _____. a. separation joints b. control joints c. expansion ... Started by geoffrey	3 Replies 61 Views	Jul 26, 2018 by cclemon1
The two common winding configurations for 3 phase motors are: A) Wye and delta. B) Alpha and ... Started by j.rubin	1 Replies 28 Views	Jul 26, 2018 by gabrielle_lawrence
Compared to single phase motors, three phase motors are: A) More complicated and use more ... Started by urbanoutfitters	1 Replies 50 Views	Jul 26, 2018 by macagnavarro
To reverse the rotation of a three phase motor: A) Reverse any two power legs going to the motor. ... Started by asmith134	1 Replies 52 Views	Jul 26, 2018 by jojobee318
If one of the power legs feeding a three phase motor is interrupted while the motor is operating: ... Started by ericka1	3 Replies 46 Views	Jul 26, 2018 by zhanghao
What type of fuse should be used in motor circuits? A) One time fuses B) Any fuse that is the ... Started by beccaep	1 Replies 53 Views	Jul 26, 2018 by Christopher
A major difference between three phase motors and single phase motors is that: A) Three phase ... Started by berenicecastro	1 Replies 73 Views	Jul 26, 2018 by juwms
The phase current of a wye wound 3 phase motor is: A) Equal to the line current. B) 1.73 times ... Started by Starlight	1 Replies 91 Views	Jul 26, 2018 by CourtneyCNorton
For air conditioners, a rise in the return air wet bulb temperature causes: A) A decrease in ... Started by TFauchery	3 Replies 20 Views	Jul 26, 2018 by aadams68
The standard AHRI A design condition used for rating unitary air conditioning equipment is: A) ... Started by khang	1 Replies 14 Views	Jul 26, 2018 by juicepod
When a pilot duty overload protecting a motor detects an overload, it: A) Breaks the circuit to ... Started by awywial	1 Replies 34 Views	Jul 26, 2018 by tanna.moeller
When an overload in a magnetic starter detects an overload: A) It breaks the line of power it is ... Started by shenderson6	1 Replies 33 Views	Jul 26, 2018 by Chelseyj.hasty
The first thing to do when testing any motor is to make sure that: A) You touch the motor to see ... Started by s.tung	3 Replies 23 Views	Jul 26, 2018 by nickk12214