1. A two-wire control may be a toggle switch.
a. True
b. False
2. A two-wire control may be any type of switch having a graduated position.
a. True
b. False
3. Two-wire control devices are generally designed to handle large currents.
a. True
b. False
4. Two-wire controls may be connected to operating coils of magnetic switches.
a. True
b. False
5. ____-volt motors require more contacts than the one contact usually provided on two-wire devices.
a. 24 b. 110
c. 120 d. 230
Name: Class: Date:
Unit 17 Two-Wire Controls
6. In the case of a(n) ____, the thermal heaters open the overload contacts in the control circuit and de-energize the
coil, thus stopping the motor.
a. overload b. imbalance
c. overflow d. disproportion
7. Typical control voltages are 120 and ____ volts.
a. 6 b. 8
c. 12 d. 24
8. Control systems that operate on ____ volts are often used in hazardous areas.
a. 24 b. 120
c. 230 d. 240
9. The ____ permits the use of intrinsically safe systems in areas that contain hazardous vapors.
a. NEMA b. NEC
c. IEEE d. UL
Name: Class: Date:
Unit 17 Two-Wire Controls