HW12 Chapter 12

Sequencers are used whenever a operating pattern is required.

• analog

• digital
• repeatable

• non-repeatable

Mechanical sequencers are often referred to as:

• drum switches

• rotary switches

• cam switches

• all of these

For the mechanical sequencer shown, the step represented by the equivalent sequencer data table file is:

• 1

• 2

• 3

• 4

A single sequencer instruction can be used the on/off operation of 16 discrete outputs.

• True

• False

To program a sequencer, binary information is entered into a word file.

• True

• False

Which of the following instructions is used to control output devices sequentially?

• SQC

• SQO

• SQL

• all of these

Each false-to-true rung transition of the SQO instruction causes the instruction to:

• set its done bit

• set its found bit

• set its error bit

• increment to the next step

Both the sequencer input (SQI) and the sequencer compare (SQC) instructions compare a value from a address (through a mask) to one of a series of data words in a sequencer file.

• position
• length

• control

• source

The found bit (FD) is one of the control elements for an instruction.

• SQO

• SQL
• SQC

• SQI

Which of the Allen-Bradley sequencer instructions can be used to automatically load data into a sequencer file?

• SQO

• SQC

• SQL

• SQI