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View Full Version : R44 Voltage regulator advice sought.


madflyer26
23rd Nov 2012, 15:38
Today I had a nightmare starting my R44 which in the process of doing I ran my battery slightly low. Once I eventually started the aircraft the ALT warning light was displayed and the AMP reading was around the 60 mark. I have checked the manual and the light is normal. Being that the battery is below the standard voltage- is it normal for the AMP reading to be so high and how long should it remain like this? I have not ground run the aircraft for more than 5 minutes as we have had a voltage regulator failure before that cooked our battery. This time the symptoms are different. Once I brought the aircraft up to 65% engine RPM the ALT warning light went out and the AMP reading remained much the same. Could someone perhaps give any advice to what has gone wrong if anything?
Kind Regards
MF

FSXPilot
24th Nov 2012, 06:16
When you say you had trouble starting what do you actually mean? Is your machine a Raven I or a Raven II. For the Raven II SL42 was released in May of this year which is a kit which helps improve starting.
If the battery was low then a high amp reading after start up would be normal and should reduce after about 10 mins.
On the 24 volt ships the maximum continuous allowed current is 64 amps.

madflyer26
24th Nov 2012, 17:04
FSX,

The aircraft is the R44 Raven 2. The problem arose from a cold start which was most likely caused by over priming! The aircraft has been subsequently started and doesn't run above 60 shown on the AMP gauge.
Regards
MF

cockney steve
24th Nov 2012, 21:35
ramming a hefty charge like that into a Lead-Acud battery, is a sure fire way to shorten it's life. Normally, I'd expect the charge rate to drop significantly after ~5 minutes.......the battery voltage rises quite fast, opposing the alternator output and thus limiting the charge-rate.....you could always stick a voltmeter across your battery to verify it's voltage "12v"...~14.2v. (double for a"24v" system ) If you've "flattened the battery seriously, to the point where it's struggling to crank, i'd recharge from an external battery-charger with a long low trickle- charge. A ballpark rate is 10% of the battery's nominal capacity....so, a 38 Amp-Hour battery should have 3 1/2 to 4 amps for about 12 hours)...it should start a bit lower, build up to it's peak rate after a couple of hours and then tail-off as the battery becomes fully charged.
heavy charge-discharge cycles take their toll on battery life!

FSXPilot
24th Nov 2012, 21:53
The Robinson maintenance manual tells you to bin the battery after two years and replace it anyway.

cockney steve
25th Nov 2012, 16:33
In automotive applications, ~5-7 years is quite normal,as is the "deep-cycle"type designed for invalid mobility chairs and the like....Electric fork-trucks and milk-floats, around 15 years!

Robbos must thrash the ar5e off a small deep-cycle type to bin it biennially:ooh: not impressed..."cheap" to buy, but the TCO must be another story altogether!

madflyer26
26th Nov 2012, 13:05
Folks,

Thanks for the advice. The apparent problem has now been fixed and the aircraft working as advertised. After ground running the aircraft for less than ten minutes the amp reading returned to the normal range. Flown for an hour today and all is well.

Kind Regards

MF