Safe max voltage from alternator

[jjonphl]

Hi guys,

I had the alternator of my Crosswind (2001) replaced couple of years back. I remember we measured it at around 13V when idle and 14-15v when revving. Last night I measured it at 17v when idle. Is this safe? How did this happen?

Thanks!

[userfriendly]

17 volts is over voltage. Voltage should be around 12 volts to 14.4 volts. Have your car checked by an auto electrician

[Ry_Tower]

Hi guys,

I had the alternator of my Crosswind (2001) replaced couple of years back. I remember we measured it at around 13V when idle and 14-15v when revving. Last night I measured it at 17v when idle. Is this safe? How did this happen?

Thanks!

No its not safe and something is wrong. Have a certified and trusted electrician check it ASAP. Dapat ganung level lang 13-14.

[yebo]

nominal voltage of each battery cell is 2.2 volts x 6 cells = 13.6 volts = required minimum output voltage of your alternator for the battery not to discharge.
voltage required to charge each battery cell = 2.6 volts x 6 cells = 15.6 volts required to charge your battery. this is the maximum allowable charging voltage. it can be lower but any higher and your battery will get overcharged.

so that means the voltage regulator should be set at a minimum of 13.6 volts and maximum of 15.6 volts (or lower).

di ba electronic naman na ang voltage regulator ng crosswind? if so then malamang shorted na yung IC nyan kaya wala nang regulation. you'll need to change the voltage regulator IC on the alternator.

[jjonphl]

Thanks for the replies. I had it checked yesterday by an auto electrical shop near us (the one that replaced the alternator years ago) & they are measured it at around 14v when idle & 16v when revved (they use an analog multimeter). It looks like my little digital multimeter is broken, it is measuring 18v when idle. In any case, I would like to have it checked by another electrician.

Do you guys know of a good one near Quezon Ave area?

Yebo: the alternator was replaced, is the IC you are referring to in the alternator or in the computer box?

Thanks.

[userfriendly]

You can try Wizards in T Morato near E Rodriguez. The IC Yebo was refering to is the IC in the alternator

[miso_honi]

Hi guys,

I had the alternator of my Crosswind (2001) replaced couple of years back. I remember we measured it at around 13V when idle and 14-15v when revving. Last night I measured it at 17v when idle. Is this safe? How did this happen?

Thanks!

where was the voltage measured from (test terminals)? the automobile alternators were designed to put out a maximum of 16 volts unregulated assuming the battery is connected, engine running and the belts is tight and in good condition. if the voltage is higher than 16 volts, there might be a loose connection on the battery terminals or the alternator output terminal or the autolink fuse.

[yebo]

the IC is on the alternator. 16 volts is only 2% above 15.6 volts, acceptable na yan since it is within the error range of the volt meter. ano ba battery mo, maintenance free or conventional? if you have a conventional battery and you are adding water more than normal then that is a sign of overcharging and you'll need to look into replacing the IC. but if not then you have nothing to worry about.

[miked]

per cell is 2.1V x 6 = 12.6V....minimum voltage of a battery with engine off is 12.6V....safest maximum is 14.4V. maintain it at greater than 14.4V and you will kill the battery (added problem in this case). Battery fluid will be lost and lamps usually burn frequently. The usual culprit is the IC inside the alternator (if built-in IC). what happened in my case is a burnt stator coil aside from a broken IC. i settled with a surplus unit.

[miked]

measurements must always be made with a digital tester not an analog for accuracy. yes, alternators can give as high as 16v or so but the problem is that the battery cannot handle it.