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YC1 · 04-24-2013, 10:06 PM

Studying the Various Bird systems for the last several years and offering what I thought was sound advice I now have to admit I just found a small tidbit of info I did not know. Funny how the issue came up today after a 9 hour trip my BIRD system was not charging my engine batteries. The generator was in use to run the air conditioners. I happened to check the voltage across the engine batteries with the engine off and they were not being charged by the converter via the bird relay. The coach batteries were getting charged.

In short, after pulling up the schematics and descriptions I came across a tidbit of information about the Bird in some of the later models. The bird passes a signal through a relay which is actually used to cut the BIRD function off if the generator is running. So trying to charge the engine batteries that has a dead alternator cannot happen on my RV. I can force it by holding the emergency start button.

In short, Starting the Generator may not Charge your engine batteries even if you have a BIRD circuit.

I may bypass that kill function. I will think on it for a few days.

tompen · 04-25-2013, 05:57 AM

Good to know. I noticed the BIRD for a diesel had an extra terminal marked GEN. Since it didn't apply to my situation I didn't research it any farther. I think my gas unit will close the isolator relay when the generator is running. But now I will have to check it.
I wonder why ??

sparkydog · 04-25-2013, 06:11 AM

YC1, It was explained to me that it doesn't charge simultaneously, but rather charge house first, then switch to chassis on time delay I'm referring to the generator operation.

Triker56 · 04-25-2013, 06:21 AM

If the alternator goes out on my Fleetwood DP.
The generator will charge the battery through the Intellitec BIRD on it.
And you can keep driving.

jettyjock · 04-25-2013, 06:29 AM

On mine the gen powers up the battery charger. If I have the battery disconnect switch in the store position it will not charge the house batteries. When the alt. charges the chassie battery to 14.1 volts the bird pulls in the battery boost sol and then charges the house batteries. When the charger is plugged in it is opposite the house batteries have to be 14.1 before it will charge the chassie battery

bruceisla · 04-25-2013, 07:02 AM

From Intellitec:

PRODUCT DESCRIPTION

Intellitec’s Bi-Directional Isolator Relay Delay-Diesel 2 performs two important functions. It provides a method of charging the coach battery from the engine alternator and charges the chassis battery from the converter when the coach is plugged into shore power. When neither battery is being charged, the batteries
are isolated from each other to prevent the loads of one battery from inadvertently discharging the other battery.
If the generator is running, the isolator is prevented from pulling in to prevent the generator and converter from operating the chassis functions, which might over-load the converter.

The assumption, from an Intellitec design point of view, is that the RV engine alternator is functioning correctly. The device wasn't intended to perform an emergency function. On my older Endeavor, the "GEN" lockout line goes back to the Genset hour meter. Yes, in the event of alternator failure you could 1) engage the "Aux Boost" switch for some period or 2) you could jumper 12vdc Chassis (assuming it wasn't totally flat) to the pick of the Isolator Solenoid or 3) directly tie the House to Chassis if the cables on the solenoid were long enough to be bolted together. None of these are a real replacement for a high output alternator. A lot would depend on the capabilility of the Inverter/Charger.

If I remember correctly, the Diesel 2 vs. the original (aka Diesel 1) had a few changes ... most significant was the constant pick/hold voltage of 12vdc in lieu of 12vdc pick with a lower (around 4vdc) hold and the use of a better continuous duty Isolator Relay (solenoid). I don't know what is installed in a newer Gas RV with Genset but I would assume the Diesel version of the BIRD would be appropriate. As far as I know, the Diesel version is not related to "Diesel" it really means "RV with Genset".

Dr4Film · 04-25-2013, 07:24 AM

On any of the charging systems mentioned above, the only way to keep your Chassis battery charged during an Alternator failure is to jumper the Battery Isolator with a short 4 or 6 gauge battery cable and then keep your generator running. You can drive across the country that way if needed well until you find a reputable shop that can rebuild your alternator.

As mentioned earlier, the BIRD system is designed to charge your House battery bank FULLY first and then it switches over to the Chassis battery. If the House batteries never get fully charged then your Chassis battery will never see any of the charging voltage from the generator.

Oh, BTW, your emergency start button or in some cases it's labeled Aux Start or something similar, by holding that in, it will also do the job, but who wants to hold that switch in for 300 or so miles. That switch activates the Battery Isolator relay. It's the same relay where I recommended installing the jumper cable temporarily.

Dr4Film ----- Richard

georgetown350 · 04-25-2013, 07:38 AM

I had an alternator go bad. To get the coach home I slipped a plastic cap under the boost switch to hold it open. After doing this, the alternator went from below 12 volts to over 13. Worked great.

RickO · 04-25-2013, 08:07 AM

Interesting. I was under the impression that when my Winnie 40DP was plugged in to shore power (or had the gennie running) the only way the chassis batteries got charged was via the Trick L Charger built in.

On those where the BIRD allows the starting batteries to be charged directly from the inverter... does the inverter provide different charging voltages to the deep cycle house batteries than to the starting batteries?

Rick

sparkydog · 04-25-2013, 08:21 AM

I initially had a problem with dead chassis batteries on a brand new coach, under warranty. There was a 300 amp fuse blown, which didn't allow the chg/inverter to charge the chassis batteries. That was replaced, all is good! So in answer to your question, at least on my coach, the charger is designed to charge house AGM' s, and then switch over to charge chassis or maintain the chassis batteries. I believe the BIRD in conjunction with 3 stage Magnum inverter/charger takes care of these different demand loads

YC1 · 04-25-2013, 09:02 AM

Quote:

Originally Posted by sparkydog

YC1, It was explained to me that it doesn't charge simultaneously, but rather charge house first, then switch to chassis on time delay I'm referring to the generator operation.

This all depends on the vintage of your setup. Mine was a late model 08 HR and the factory had Mega Tech of oregon design a replacement for the original add on. They were making the front run circuit boards so it was a natural fit. The schematic shows a small relay in addition to the ckt board. My ckt board only has three wires. The output is blocked when the generator is running.

YC1 · 04-25-2013, 09:04 AM

Quote:

Originally Posted by Triker56

If the alternator goes out on my Fleetwood DP.
The generator will charge the battery through the Intellitec BIRD on it.
And you can keep driving.

This is the reason for posting my new findings. I was actually troubleshooting mine by reviewing all the schematics and information I have and as I have many times in the ET world found one sentence in the middle explaining the circuit. Seems strange since I can bypass it with the emergency start button anyway.

YC1 · 04-25-2013, 09:09 AM

Quote:

Originally Posted by RickO

Interesting. I was under the impression that when my Winnie 40DP was plugged in to shore power (or had the gennie running) the only way the chassis batteries got charged was via the Trick L Charger built in.

On those where the BIRD allows the starting batteries to be charged directly from the inverter... does the inverter provide different charging voltages to the deep cycle house batteries than to the starting batteries?

Rick

No, it parallels the batteries and treats them as one large bank of batteries.

cbeierl · 04-25-2013, 09:12 AM

Quote:

Originally Posted by RickO

Interesting. I was under the impression that when my Winnie 40DP was plugged in to shore power (or had the gennie running) the only way the chassis batteries got charged was via the Trick L Charger built in.

...
Rick

Your impression is correct for your Winnebago coach (which does not use the BIRD). The Trik-L-Start will provide up to a 5A charge to the chassis batteries whenever the coach/house batteries are being charged. When the engine is running or the Aux Start switch on the dash is engaged the batteries are connected together via the Aux Start Solenoid.