Alternator and external regulator issue

[Rumrace]

I believe leaving it on is like leaving your car ignition on but not starting. In a car this damages the alternators diodes and the coils. If this circuit has to be on when horn instruments lighting is on its completely wrong.

[GordMay]

Old copies of The 12 Volt Doctor's Alternator Book are available for sale, at numerous internet sites; but there are also FREE downloads available, on-line:
“The 12 Volt Doctor's Alternator Book” ~ by Edgar J. Beyn
➥ https://www.scribd.com/doc/119790895...LTERNATOR-BOOK
➥ https://archive.org/details/12voltdoctorsalt00beyn

Also by Edgar Bbeyn:
“The 12 Volt Doctor's Practical Handbook for the boat’s electrical system”
➥ http://www.melody-in-blues.org/downl...lthandbook.pdf

***


A VERY BASIC Guide to Alternator Testing: [from 2003]

GENERAL INSPECTION:

A loose drive belt can cause slipping and undercharging, noise and vibration, and premature belt wear. An over-tight belt may cause bearing wear.

Look at and feel the drive-belt, examining for cracking, fraying, glazing, and/or separation. Replace damaged belt(s).

Test the belt tension by firmly depressing midway between the sheaves. The belt should deflect between 1/4" (for sheaves with 7" - 10" centerline separations) and ½" for 12" - 16"separations). Adjust tension as necessary.

Inspect all wiring and terminations. Wire should be adequately sized for the application (see “Ohm’s Law & Boats”), secured at least every 18", and run as high and dry as possible. Termination s must be clean (no visible corrosion), and tight. Examine the wire for thermal (melting or charred insulation) or mechanical damage (frayed, cracked, or missing insulation).
Replace damaged or undersized wire, and replace or repair inadequate terminations.

ALTERNATOR VOLTAGE TESTS:

1. Set Voltmeter to DC Volts (20V scale), and connect the DC Voltmeter test leads to the battery post (Red lead to Positive Post, and Black(or Yellow) to Negative). With engine “off”, read and note battery voltage (see “Battery Testing”).

2. Start the engine, and at “Idle” RPM, check the voltmeter reading. At very low speeds the alternator output may be lower than the regulator setting; hence you will expect to read the battery voltage.

3. Increase engine RPM, and note increasing voltage reading to a maximum of about 14.2 volts (12V Nominal System - expect ± 29.5V in 24V system).

If no voltage increase noted, you likely have a bad voltage regulator, or poor wiring
(Alt’ to Batt.). Go on to test 3B.

If Voltage increases go on to test 4.

3B. With engine “off”, connect Positive test lead to Alternator Output (“B+”, or “A”), and Negative Lead to the Negative Ground Post (“Neg”, or “E”) of Alternator. Start engine. If Voltage increases with increased RPM, your regulator is OK, and the problem is in the wiring. Go on to test 3C.

3C. Discharge the Battery to less than 12.5 Volts. Check for Voltage drop between the Alternator and Battery, as follows..
Connect the Positive Test Lead to the Alternator Positive Output Terminal (B+) and the Negative Lead to the Positive Battery Post. Crank the engine, and increase RPM to a fast idle. Observe Voltage. If the voltage climbs to as much as 0.02 Volts (or more), the positive cable has a high resistance. Repair or replace cable.

Check for voltage drop in the negative cable, as above - but: connect the Positive Lead to the Alternator’s Negative Output Terminal, and the Negative Lead to the Negative Battery Post. Analyze as above.

[goboatingnow]

Originally Posted by Rumrace

I believe leaving it on is like leaving your car ignition on but not starting. In a car this damages the alternators diodes and the coils. If this circuit has to be on when horn instruments lighting is on its completely wrong.

None of this damages modern cars or regulators

[markcouz]

Surely a simple solution is to have an automotive relay powered by the ignition switch that only sends 12v to the field terminal when the ignition switch is on.

[Stu Jackson]

Originally Posted by markcouz

Surely a simple solution is to have an automotive relay powered by the ignition switch that only sends 12v to the field terminal when the ignition switch is on.

That's true, but wouldn't it be necessary only if the locations or loads compared to existing wire sizes of the components were distanced to require yet an additional device? The ignition wire to the external regulator is already the I/O for the regulator, or at least it should be, no?

[Bowdrie]

Not usually a big deal to add a pressure switch to the engine that senses oil pressure.
The runs are short, a really foolproof way to turn on/off the field.

[Jack Chapman]

Originally Posted by markcouz

Surely a simple solution is to have an automotive relay powered by the ignition switch that only sends 12v to the field terminal when the ignition switch is on.

but the whole point of the regulator is that it regulates the field wire in accordance with the charging state of the batteries. If it is just always on, like it seems to be with mine, then I think the alternator will just produce full whack all the time that the engine is on.

[goboatingnow]

Originally Posted by markcouz

Surely a simple solution is to have an automotive relay powered by the ignition switch that only sends 12v to the field terminal when the ignition switch is on.

Good god , that’s not going to work. You need regulation.

[rgleason]

This is the same regulator as the old Cruising Solutions Alpha. I still have mine as a spare. Perhaps I have the wiring diagram. I will look. It is a good regulator for its time. We used it about 10-12 years.

[GordMay]

Originally Posted by rgleason

This is the same regulator as the old Cruising Solutions Alpha...

Cruising Equipment Co ALPHA Alternator Regulator
INSTALLATION MANUAL ➥ https://www.cruisingequipment.com/pr...lpha/alpha.pdf

MasterVolt ALPHA PRO ALTERNATOR & REGULATOR
OWNER'S MANUAL➥ http://productimageserver.com/litera...al/69995OM.pdf

[mstr_cmdr]

Originally Posted by GordMay

Old copies of The 12 Volt Doctor's Alternator Book are available for sale, at numerous internet sites; but there are also FREE downloads available, on-line:
“The 12 Volt Doctor's Alternator Book” ~ by Edgar J. Beyn
➥ https://www.scribd.com/doc/119790895...LTERNATOR-BOOK
➥ https://archive.org/details/12voltdoctorsalt00beyn

Also by Edgar Bbeyn:
“The 12 Volt Doctor's Practical Handbook for the boat’s electrical system”
➥ http://www.melody-in-blues.org/downl...lthandbook.pdf

***


A VERY BASIC Guide to Alternator Testing: [from 2003]

GENERAL INSPECTION:

A loose drive belt can cause slipping and undercharging, noise and vibration, and premature belt wear. An over-tight belt may cause bearing wear.

Look at and feel the drive-belt, examining for cracking, fraying, glazing, and/or separation. Replace damaged belt(s).

Test the belt tension by firmly depressing midway between the sheaves. The belt should deflect between 1/4" (for sheaves with 7" - 10" centerline separations) and ½" for 12" - 16"separations). Adjust tension as necessary.

Inspect all wiring and terminations. Wire should be adequately sized for the application (see “Ohm’s Law & Boats”), secured at least every 18", and run as high and dry as possible. Termination s must be clean (no visible corrosion), and tight. Examine the wire for thermal (melting or charred insulation) or mechanical damage (frayed, cracked, or missing insulation).
Replace damaged or undersized wire, and replace or repair inadequate terminations.

ALTERNATOR VOLTAGE TESTS:

1. Set Voltmeter to DC Volts (20V scale), and connect the DC Voltmeter test leads to the battery post (Red lead to Positive Post, and Black(or Yellow) to Negative). With engine “off”, read and note battery voltage (see “Battery Testing”).

2. Start the engine, and at “Idle” RPM, check the voltmeter reading. At very low speeds the alternator output may be lower than the regulator setting; hence you will expect to read the battery voltage.

3. Increase engine RPM, and note increasing voltage reading to a maximum of about 14.2 volts (12V Nominal System - expect ± 29.5V in 24V system).

If no voltage increase noted, you likely have a bad voltage regulator, or poor wiring
(Alt’ to Batt.). Go on to test 3B.

If Voltage increases go on to test 4.

3B. With engine “off”, connect Positive test lead to Alternator Output (“B+”, or “A”), and Negative Lead to the Negative Ground Post (“Neg”, or “E”) of Alternator. Start engine. If Voltage increases with increased RPM, your regulator is OK, and the problem is in the wiring. Go on to test 3C.

3C. Discharge the Battery to less than 12.5 Volts. Check for Voltage drop between the Alternator and Battery, as follows..
Connect the Positive Test Lead to the Alternator Positive Output Terminal (B+) and the Negative Lead to the Positive Battery Post. Crank the engine, and increase RPM to a fast idle. Observe Voltage. If the voltage climbs to as much as 0.02 Volts (or more), the positive cable has a high resistance. Repair or replace cable.

Check for voltage drop in the negative cable, as above - but: connect the Positive Lead to the Alternator’s Negative Output Terminal, and the Negative Lead to the Negative Battery Post. Analyze as above.

Just having a "flick" through "The 12 Volt Doctor's Practical Handbook for the boat’s electrical system", p 18.
The symbology for the batteries is incorrect - the negative side of a cell should be the smaller line; and, the positive side should be the larger.
Hmm - I wonder what else is amiss.

[Dalestr]

You might actually like to verify that it is capable regulating the output voltage with a well-charged battery. That may require it go thru the bulk charge period (full charge) and then into acceptance mode where in theory, a fairly high fixed charge voltage is supplied (usually just over 14V) This requires voltage regulation as does float mode, where it must be actively regulating. If it is properly regulating then the field voltage would rapid switching on and off (due to the inductive load these would roughly resemble square waves). Easy to see with an O'scope but not with a digital meter. There would also be a sizable AC voltage component when actively regulating, not seen during bulk charging.

You could also install an ammeter in the field circuit and verify there actually is current when "ignition" off. Depending on size of alternator this could be anywhere between 2.5A and 8A when normally engaged with engine still and ignition on. With your "ignition" off there should be 0 current.

The output transistor of the regulator may be a mosfet or bipolar transistor (often in Darlington configuration) but it won't a be a Field Effect transistor (FET).

[pbmaise]

Aboard my vessel it came with an external alternator controller that some people swear by. Yes there was a switch on my panel to manually turn on the alternator. If I forgot to turn off that switch, I found the alternator was draining my batteries when the engine was off.

When my alternator died, I was so confused about bypassing the internal alternator that the new alternator already had on it, I decided the easier thing to do was bypass the external alternator. Everything worked just fine. Perhaps it wasn't the perfect charging profile, however, I was using lead acid batteries which is exactly that the alternator was designed to charge.

[goboatingnow]

Originally Posted by pbmaise

Aboard my vessel it came with an external alternator controller that some people swear by. Yes there was a switch on my panel to manually turn on the alternator. If I forgot to turn off that switch, I found the alternator was draining my batteries when the engine was off.



When my alternator died, I was so confused about bypassing the internal alternator that the new alternator already had on it, I decided the easier thing to do was bypass the external alternator. Everything worked just fine. Perhaps it wasn't the perfect charging profile, however, I was using lead acid batteries which is exactly that the alternator was designed to charge.

Car alternator regulators are of course not actually designed to charge batteries at all. They are designed to power the cars dc systems.

[smac999]

Originally Posted by Jack Chapman

Yes, the field wire (not from the alternator) has 12v even when the regulator is switched off. So the +12v IN wire seems to be connecting to the field wire somewhere inside the box. And if that is the case then I sort of doubt the regulator is doing any actual regulation of the field output at all.

I'll take a look under the cover when I go down to the boat today, but unless it is something easy, then it sounds like a need a new regulator.

Get yourself a balmar 614 with alt temp sensor.