Charging system weak?

[Charles Hines]

I have a 2022 Coleman 400 utv. I have added a heater with a 3 speed fan. I notice that while running with nothing on, the battery voltage gets to about 13,7 volts when funning at speed. If I turn on the lights, the voltage drops to about 12.3,if I turn on the heater fan with the lights on, the battery light will come on. I have replaced the battery with a higher capacity one and have replaced the regulator/rectifier, both have made no difference. I have measured the ac voltage at 22 vac at idle across all 3 phases, so the stator is charging. I have never had any issues with not starting or running poorly due to low voltage. Just wondering if there is anything I can do to increase the voltage from the regulator or is this just a underachieving system?
 

[Bill Hughes]

1. Its' not a car, this is a motorcycle engine with a small stator charging system. You can't expect to run high wattage accessories like a heater or huge light bars on these things . That will overwhelm the charging system, drain your battery an stop your engine. Could damage the charging system and voltage regulator too. You only have about 10 amps extra to run any accessories including lights. 

[Charles Hines]

The only non stock item is the heater,which is designed for this utv. 

[Steve G.]

59 minutes ago, Charles Hines said:

The only non stock item is the heater,which is designed for this utv. 

Designed for doesn't necessarily mean the stator output can handle the load as Bill said. What is the power rating of the heater, current x voltage?

[Ben1098]

Just a idea about an senior and good aftermarket charging system company that has salvaged some new sales failures for a friend.  Charging system puked in a few hours after purchase.  That takes the shine off of a new unit.  Rick's to the rescue.

Design wise, the stator is made "light" on the windings so the regulator can be lower cost build....i.e.....cheap as is the "power runs in the OEM harness.  The regulator used is a waste excess charging current system.  The excess current is shunted to ground over and above that required for the 13.6V ish to charge the battery and run accessories.  A higher wattage stator will need a higher wattage regulator.  $$$$$$$$

We used Rick's for years.....the latest "problem" I heard about was a xmxmxmx unit that had a strong stator but the voltage regulator used for certain models dies and the regulator is on national back order.  NEWLY SOLD UNIT IS UNUSABLE and NO LIGHT AT THE END OF THE TUNNEL.  Rick's built up a "custom" regulator to fix the problem that xmxmxmx Engrs could not or would not fix.  It is a multi-year screw up so there was time if Rick's worked up a winner in a week why not the OEM Engrs.

Contact Rick's and spec a hotter stator and a matching better regulator.  Warning:  I have had to beef up the stator wires and regulator supply and gnd wires over the stock OEM wiring harness for some real headlights on street bikes.....too much drop in the cheap wiring runs.  Just saying, you might have to do some harness upgrades also. 

Rick's Motorsports Electrics       ricksmotorsportelectrics.com

[Bill Hughes]

Electric power comes from mechanical power. The charging system is small so it doesn't rob too much horsepower, not because it's cheaper to do it this way. 

[Steve G.]

1 hour ago, Bill Hughes said:

Electric power comes from mechanical power. The charging system is small so it doesn't rob too much horsepower, not because it's cheaper to do it this way. 

I imagine both are considerations when deciding on finished product. Cost vs. payoff always come into play. More electric power would mean increasing the horsepower, or losing performance, and designing the circuits to handle the increased power capacity. More expensive all the way around.

[aefron88]

On 11/15/2023 at 5:20 PM, Charles Hines said:

I have a 2022 Coleman 400 utv. I have added a heater with a 3 speed fan. I notice that while running with nothing on, the battery voltage gets to about 13,7 volts when funning at speed. If I turn on the lights, the voltage drops to about 12.3,if I turn on the heater fan with the lights on, the battery light will come on. I have replaced the battery with a higher capacity one and have replaced the regulator/rectifier, both have made no difference. I have measured the ac voltage at 22 vac at idle across all 3 phases, so the stator is charging. I have never had any issues with not starting or running poorly due to low voltage. Just wondering if there is anything I can do to increase the voltage from the regulator or is this just a underachieving system?
 

Are you talking about an electric heater? if yes its likely too much current. There might be 10 amps of available current coming out of the rectifier that isn't already claimed by the ECU and factory lights. 10 amps @ 12V  = 120 Watts, which is about what an electric heating pad runs. If you're talking about a fan for a engine coolant based heater it's probably ok.

If you have accessories and the running voltage is below 13.5V you have too much stuff attached. If the battery light comes on it means the battery is actively being discharged while running.

Stator based charging systems on these things and tractors etc are really meant to power the ECU and factory systems not to provide a lot of extra power for other stuff, it's not like the alternator on a car.