Mitsubishi FR - S500 instruction manual O signals, Parameter setting, 105, Entry Description

(4) I/O signals

Signal		Terminal Used	Function	Description
	X14	Depending on	PID control	Turn on X14 to exercise PID control.
		Pr. 60 to Pr. 63	selection
Input	2	2	Set point input	Enter the set point for PID control.
	4	4	Process value	Enter the 4 to 20mADC process value
			input	signal from the detector.
	FUP		Upper limit output	Output to indicate that the process value
				signal exceeded the upper limit value.
	FDN		Lower limit output	Output to indicate that the process value
Output		Depending on		signal exceeded the lower limit value.
		Pr. 64, Pr. 65	Forward (reverse)	"Hi" is output to indicate that the output
	RL			indication of the parameter unit is forward
			rotation direction	rotation (FWD) or "Low" to indicate that it is
			output
				reverse rotation (REV) or stop (STOP).

Enter the set point across inverter terminals 2-5 or in Pr. 93 and enter the process value signal across inverter terminals 4-5.

To exercise PID control, turn on the X14 signal. When this signal is off, PID control is not exercised.

Item	Entry	Description
		Set 0V as 0% and 5V as 100%.	When "0" is set in Pr. 73 (5V
	Across		selected for terminal 2).
Set point	terminals 2-5	Set 0V as 0% and 10V as 100%.	When "1" is set in Pr. 73 (10V
			selected for terminal 2).
	Pr. 93	Set the set point (%) in Pr. 93.
Process	Across	4mA DC is equivalent to 0% and 20mA DC to 100%.
value	terminals 4-5

(5) Parameter setting

Parameter	Name	Setting	Description
Number
88	PID action	20	For heating, pressure control, etc.	PID reverse action
	selection	21	For cooling, etc.	PID forward action
			If the proportional band is narrow (parameter setting is
			small), the manipulated variable varies greatly with a
	PID		slight change of the process value. Hence, as the
		0.1 to 999%	proportional band narrows, the response sensitivity
89	proportional
	band		(gain) improves but the stability	deteriorates, e.g.
			hunting occurs.
			Gain K = 1/proportional band
		- - -	No proportional control

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