Solid State Hall-effect Sensors

Adjustable Hall-Effect Under-speed Detectors

SS421 Series

2 Honeywell

• Sensing and Control

Figure 1. SS421H Timing Diagram

Td is the time delay after the pulses/min go below the trip point. Td is set by the external RC.

Tp is the time delay after the pulses/min go above the trip point. Tp is less than 20% of Td.

LOW

HIGH

VOLTAGE

SPEED

<Td

PASS

FAIL

NON-INV

NO DELAY

Td

<Td

HIGH

LOW

Td

Tp

Tp

TIME AXIS

SUPPLY VOLTAGE

APPLIED AND HELD

NON-INV

DELAY

Figure 2. SS421L Timing Diagram

Td is the time delay after the pulses/min go below the trip point. Td is set by the external RC.

Tp is the time delay after the pulses/min go above the trip point. Tp is less than 20% of Td.

LOW

HIGH

VOLTAGE

SPEED

<Td

PASS

FAIL

INV

NO DELAY

INV

DELAY

Td

<Td

LOW

Td

Tp

Tp

TIME AXIS

SUPPLY VOLTAGE

APPLIED AND HELD