03 Monaco electric question

[Wrknrvr]

 Regular customer over the years changed his chassi batteries.

 

1.  Now inverter charges at 12.4 Vdc. It will produce amps.

 

 2. Try to do a hard reset which is remove 12vdc power from inverter and clean battery terminals. Time of batteries disconnected . Maybe 45 minutes. It still will not charge above 12.4.

 

 3. Test charging from engine .     17.7 Vdc.      Yes 17.7 Vdc      Order new alternator. I needed to remove alternator to get make and model. 

 

 4. Ok next step is to do a hard reset on the inverter by removing 12vdc and all 110vac from inverter along with all in and out 110 volt ac of the inverter.

 

 5. After 24 hrs reconnect inverter back in operation. Charging 13.6 at good amps.

 

 6. Inverter is still working when new alternator arrives. Disconnect all 12 Vdc to alternator. Install new alternator. It is doing its thing at about 14. Vdc and things are looking good.

 

 7. Start checking lights and such for customer on exterior for operation. Find head lights are a problem. Then front marker lights. While at the font doc control area for fuses under the drivers side front panel. 17.7 Vdc again.

 

8. Yep 17.7 Vdc from alternator. Do some checking for connection.

 

 9. 6 pm Friday go home and think.

 

10. 800 bucks for the alternator.   What is happening.

 

 Out for other fun in RV repair today.

 

 Customer was to leave Friday am,

 

trying to smile,.  Thanks in advance for help.    Vern

[Smitty77_7]

Electronics are always fun to debug - NOT:)! 

I'll mostly suggest you post this question on the Monaco Forum, of IRV2. Add the model of the Monaco, and to be safe, add the model of the inverter/charger. 

Is their a stand alone regulator between the alternator and the battery? 

Loose or dirty contacts between say the grounds, or battery terminals. And even corrosion down inside of where wires slip into connectors (Connectors can be nice and clean, but the wire connection in a crimped on connector can be corroded.) - can cause strange behavior.

Getting close to a full moon too... 

Best of luck to you, and getting your customer off on the road...

Smitty

[Kirk W]

This one is way beyond my skill level!

[oldjohnt]

 As you well know, 12.4 volts DOES NOT EQUATE TO CHARGING. A full charged so called 12 volt battery stabilized at rest should read near 12.6 volts and in order to pump charging current through a 12 volt battery the charger has to be at a higher voltage and typical battery voltage while subjected to a charger may be 13+ up to 14 + volts. Of course, that 17 volts seems high and leads one to suspect a faulty regulation circuit. However, the open unloaded voltage of say an alternator or charger may exceed these values and its to what voltage it is once connected to a load that matters most.  If there's absolutely no load on an alternator it could register higher then expected voltage. 

 Sorry, I just cant say from here what's going on nor offer much advice. Let us know what happens

John T

[Ray,IN]

Excessive resistance in the circuit can cause the voltage regulator to sense low charging voltage, the regulator then might cause an overcharging condtion by increasing flow to the rotor.

Just one possibility.

[Wrknrvr]

 Well now this has been frustrating to work on this RV. But this is what I have accomplished.

 First thing was with a hard reset for 24 hours has the inverter back to its proper way. 

 So I was just looking yesterday in the am and noticed a wire that I thought may have a connection problem. It had a splice about three inches from the end and attached to the 12vdc on one side of a 1000 amp seliniod along with heavy cables. So I removed that connection and installed new parts.

 I called Prestolite corporation help line for tech support. He was not concerned about 17+ volts yet. But he said to connect the external voltage sense terminal to the positive on the alternator. So since I cannot see the back of the alternat I use a remote camera and there is no remote sense labeled.    Blank.  Blank.   Blank.....

 But there is a post with a wire on it that is labeled Duval.     Now what is Duval. I had installed a new rebuilt alternator. Rebuilt by Wilson. Reputable nation wide service and warranty.

 Now the Prestolite guy said it is probably not sensing voltage. While talking to the Wilson tech line he asked for the model number of the alternator. Cannot read sticker while alternator is mounted. Called auto parts store for part number .     They are busy but still have the old alternator. Will call with part number later.

 

 I did tell the customer to keep a sheet that came with the alternator . Yes there is a number.

 

 Wilson guy says that number is for a motor home. Yes that's it.      Now tech guy says that Duval label is the same as a sense post.

 

 Now it is finally coming together sorta. Now start the engine and hit the bost switch.

 

 It is now charging 14.3 on the chassis battery. Leave off the boost switch. High voltage again.

 

 Check battery isolator and charge line from isolator to the batteries has 12.4 volts when center charge post is 17volts.

 

 Swop battery isolated end for end and ----------------       Works.

 

 Now the house batteries are not charging. But they are not at17 Vdc.

 

 Order new battery isolator to be installed this am.

 

Did not sw------ much.

 

 Glade he is leaving tomorrow,       Vern 

[Wrknrvr]

 Now Kirk maybe you should stop buy sometime when I am working on something like this.

 

 Customer was smiling yesterday. He was supposed to have left last Friday.

 

 Safe Travels,.   Vern

[Kirk W]

4 hours ago, Wrknrvr said:

Now Kirk maybe you should stop buy sometime when I am working on something like this.

I do remember a few days like yours back when I was making a living in field service.