Test 3

Question 0

Latching relays are normally used when it is necessary for:

Answer 0

Contacts to stay open and/or closed even though the coil is only energized for a short time.

Question 1

Will both programmed and real-world relays, if latched, remain latched if power is lost and then restored?

Answer 1

Both will retain

Question 2

Explain why an MCR is often used with off-delay timers.

Answer 2

So the circuit can be shut down completely without waiting for the OFF delay timers to timeout

Question 3

An MCR can be used to control:

Answer 3

Selected circuit rungs.

Entire circuits.

Question 4

When using PLCs, NEMA recommends that consideration be given to stop functions independent of the PLC. Explain briefly why this recommendation is made.

Answer 4

Hardware safety circuit should always be wired to a PLC to provide a STOP independent of the program.

Question 5

Define the word retentive.

Answer 5

Keeps value after power loss

Question 6

Jump

Label

Answer 6

JMP

LBL

Question 7

Jump to Subroutine
Subroutine
Return

Answer 7

JSR
SBR
RET

Question 8

Temporary End Instruction
Always False Instruction
One-Shot Instruction

Answer 8

TND
AFI
ONS