[Nut-upsuser] unacceptable utility voltage rate of change

[Vieri]

Hi,

One of my APC devices reports: "unacceptable utility voltage rate of change".
I believe it has something to do with input voltage fluctuating too fast maybe even beneath or over the input voltage thresholds.
Should I worry about this?
should I measure input voltage? (I suppose I'd need more than multimeter readings. Maybe an oscilloscope or a multimeter that can record statistics? - I'm no expert in this field...)

battery.alarm.threshold 	: 	0
battery.charge 	: 	100.0
battery.charge.restart 	: 	00
battery.date 	: 	09/02/08
battery.packs 	: 	000
battery.runtime 	: 	960
battery.runtime.low 	: 	120
battery.voltage 	: 	55.05
battery.voltage.nominal 	: 	048
device.mfr 	: 	APC
device.model 	: 	SMART-UPS 5000 RM DL4
device.serial 	: 	AS0836160289
device.type 	: 	ups
driver.name 	: 	apcsmart
driver.parameter.pollinterval 	: 	2
driver.parameter.port 	: 	/dev/UPS-1
driver.version 	: 	2.6.3
driver.version.internal 	: 	3.0
input.frequency 	: 	50.00
input.quality 	: 	FF
input.sensitivity 	: 	H
input.transfer.high 	: 	253
input.transfer.low 	: 	196
input.transfer.reason 	: 	unacceptable utility voltage rate of change
input.voltage 	: 	226.2
input.voltage.maximum 	: 	226.2
input.voltage.minimum 	: 	226.2
output.voltage 	: 	226.2
output.voltage.nominal 	: 	230
ups.delay.shutdown 	: 	020
ups.delay.start 	: 	000
ups.firmware 	: 	112.1DL4.I
ups.id 	: 	UPS_IDEN
ups.load 	: 	039.0
ups.mfr 	: 	APC
ups.mfr.date 	: 	09/02/08
ups.model 	: 	SMART-UPS 5000 RM DL4
ups.serial 	: 	AS0836160289
ups.status 	: 	OL
ups.temperature 	: 	022.5
ups.test.interval 	: 	1209600
ups.test.result 	: 	NO

Thanks,

Vieri