Hach sc1000 user manual Function set to FREQ. Control / Linear working mode, 103

Advanced Operations

PWM CONTROL/PID CONTROL

INPUT VALUE

Displays the process value read from the selected source after it has been processed by the internal formula parser (if prompted).

With the PWM CONTROL/PID CONTROL the relay generates a PWM (Pulse-Width-Modulated) signal with an on/off ratio trying to control the process value.

6.3.3.8 Function set to FREQ. Control / Linear working mode

FREQ. Control / Linear

		Default value: LINEAR
		There are two SET FUNCTION menus.
SET FUNCTION		First menu: Selects the basic function of the relay.
		Second menu: Defines whether the output frequency signal is depending linear to the process
		value or the output frequency signal is working as a PID controller.
	LINEAR	Signal is linearly dependent on the process value.
	PID CONTROL	Signal works as a PID controller.
		Default value: 0 seconds
SET TRANSFER		Sets a substitute output frequency when some error conditions are detected in the selected
		source or if the source is missing.
		Default value: 1 second
HIGH ALARM		Sets the duration cycle in seconds of the output frequency when the process value reaches the
		HIGH ALARM limit.
		Default value: 10 seconds
LOW ALARM		Sets the duration cycle in seconds of the output frequency when the process value reaches the
		LOW ALARM limit.
		Default value: 15
HIGH ALARM		Determines at which process value the duration cycle of the output frequency has got the value
		set at HIGH ALARM.
		Default value: 5
LOW ALARM		Determines at which process value the duration cycle of the output frequency has got the value
		set at LOW ALARM.
INPUT VALUE		Displays the process value read from the selected source after it has been processed by the
		internal formula parser (if prompted).

103