Mitsubishi FR - S500 instruction manual 100, Where, a =

					(%)
	operation level (%)				compensation factor		operation level (%)	Setting example
Stall prevention		Pr.22				Stall prevention			(Pr.22=150%,
		When Pr.23 ="- - -"		Reduction ratio				150	Pr.23=100%, Pr.28=60Hz)
								112.5
								90
			Pr.23					75
		Pr.28	120Hz Output					0	6080100120 Output
			frequency (Hz)						frequency (Hz)

<Setting>

Generally, set 150% (factory setting) in Pr. 22 "stall prevention operation level". Setting "0" in Pr. 22 disables stall prevention operation.

To reduce the stall prevention operation level in the high frequency range, set the reduction starting frequency in Pr. 28 "stall prevention operation reduction starting frequency" and the reduction ratio compensation factor in Pr. 23.

Calculation expression for stall prevention operation level

Stall prevention operation level (%) = A + B × [				Pr. 22 - A	] × [	Pr. 23 - 100	]
				Pr. 22-B		100
where, A =	Pr. 28 (Hz) × Pr. 22 (%)	, B =	Pr. 28 (Hz) × Pr. 22 (%)
	output frequency (Hz)			120Hz

By setting "- - -" (factory setting) in Pr. 23, the stall prevention operation level is constant at the Pr. 22 setting up to 120Hz.

REMARKS

When the fast-response current limit is set in Pr. 21 "stall prevention function selection" (factory setting), do not set any value above 170% in Pr. 22. The torque will not be developed by doing so.

If the Pr. 22 value is set to higher than 170%, make setting in Pr. 21 to disable the fast-response current limit.

In vertical lift applications, make setting so the fast-response current limit is not cativated. Torque may not be produced, causing a gravity drop.

CAUTION

Do not set a small value as the stall prevention operation current. Otherwise, torque generated will reduce.

Test operation must be performed.

Stall prevention operation during acceleration may increase the acceleration time. Stall prevention operation during constant speed may change the speed suddenly. Stall prevention operation during deceleration may increase the deceleration time, increasing the deceleration distance.

to Refer to to (page 61)

70