Whirlpool MAH3000 Definitions, Start/Stop Input, See Push-To-Start/Line Relay Operation

machine control interprets this loss of power as an indication that the water level has reached the full level.

When the washer is at the "full" level and the timer is set in a Prewash Tumble, Main Wash Tumble, Light Wash Tumble, or Rinse Tumble increment, the machine control will begin the sequence timing defined for each cycle and fabric selection setting (See Cycle Sequence

Definitions).

During the drain and spin increments after the main wash, first rinse, second rinse, and ex- tra rinse increments, the wash side circuit in the pressure switch is closed. When the wa- ter level drains below the wash full level, the circuit will close and energize the pressure switch input. The machine control interprets this signal (not to energize the water valve outputs) to measure how quickly the washer is draining. If the machine control commands a spin speed above 51 rpm before the pres- sure switch input is energized, it will drop the speed to 0 rpm and hold there until the pres- sure switch input is energized. An additional delay equal to the length of time elapsed will occur before the pressure switch input is en- ergized. If four minutes elapse without the pressure switch input being energized, the machine control will energize the timer mo- tor output to advance the timer into the next increment and continue with the cycle.

START/STOP INPUT

The start/stop input is energized by the mo- mentary Push-to-Start/Stop Switch. If this in- put is energized when a cycle is in progress, the machine control will disengage the line relay, both water valve output signals, the door lock wax motor signal, the timer motor out- put signal, and the on-light output signal. If this input is energized when a cycle is not in progress, the machine control will energize the line relay and begin the cycle sequence as defined by the timer and user input switches

(See Push-To-Start/Line Relay Operation).

TACH INPUT

The tach input is a feedback signal from the motor control. It provides eight pulses per revolution of the switched reluctance motor. The motor runs at 14 times the speed of the spinner (14:1 belt ratio). The tach input is used for monitoring speed and out-of-balance de- tection (See Tachometer Circuit Diagnostics).

If the machine control commands a motor speed and direction but does not sense a tach input signal within five seconds, it will disen- gage the line relay to stop the washer. This generally indicates a locked rotor or a mal- function in the motor control.

If the machine control senses a tach input sig- nal when it is not commanding the motor to run, it will disengage the line relay to stop the washer.

If the machine control commands a coast down from final spin speed but is still receiv- ing a tach input signal after two minutes, it will disengage the line relay to stop the washer.

TEMPERATURE SENSOR INPUT

A thermistor is located in the water valve to monitor the blended incoming water tempera- ture. The machine control uses this input sig- nal to regulate the water temperature with the warm or cold wash or warm rinse tempera- ture selections (See Water Valve Outputs).

TIMER INPUTS

The Timer Input signals are energized through the cams in the timer. The timer operates with a 30 second drive cycle and a 5.8 second ad- vance time (See Timer Input Charts).

WATER TEMPERATURE INPUTS

The Water Temperature inputs are two sepa- rate signals defined by a user input switch on the control panel. The machine control inter- prets these signals to determine what the wa- ter temperature should be for each fill (See

Water Valve Outputs).

16008373-01	SECTION 1. GENERAL INFORMATION	1-7
	© 1998 Maytag Corporation