Hitachi L100 instruction manual Output Deviation for PID Control, PID loop error is defined as

L100 Inverter

4–21

Output Deviation for PID Control

	The PID loop error is defined as the			Error			Process variable
	magnitude (absolute value) of the differ-			(SP-PV)
	ence between the Setpoint (target value)			set	C44		Setpoint
	and the Process Variable (actual value).
				value	C44
	When the error magnitude exceeds the
	preset value for C44, the [OD] terminal
	signal turns on. Refer to the PID loop				[OD]
	section on page 4–27 for more on PID loop					ON	ON
					Signal
	operation.						time
Option	Terminal	Function Name	Output			Description
Code	Symbol		State

04

OD

Output deviation for

ON

when PID error is more than the set threshold for

PID control

the deviation signal

OFF

when PID error is less than the set threshold for

the deviation signal

Valid for outputs:

11, 12, AL0 – AL2

Example:

Required settings:

C44

Inverter output

OD

Notes:

terminal circuit

• The default difference value is set to 3%. To change

this value, change parameter C44 (deviation level).

H

O

OI

L

FM

CM2

12

11

+	RY
–

See I/O specs on page 4–5.

NOTE: The example circuit in the table above drives a relay coil. Note the use of a diode to prevent the negative-going turn-off spike generated by the coil from damaging the inverter’s output transistor.

Operations and Monitoring