Late Model CD-25 Battery/Charger Configuation

[Bill.Secure]

My 2007 CD-25 came with a Guest 5-5-10 three output charger but I only have two batteries. I could see color coded wires corresponding to the diagrams in the 2006 manual but that manual showed a Guest 5-5 charger, not the 5-5-10.

I e-mailed the factory and just received a call back from them. I was told that the 10 amp connection from the charger was not in use but was run as a red 10 gauge wire to the transom (but was not connected to anything at that point). I was also told that the 10 amp Guest charger output was for adding a third battery (and that some of their cruisers were delivered that way).

I've been wondering about this because I was concerned that when I was at the dock under shore power, I could easily run down the house battery. The instructions with the Guest charger state that the battery selector switch should be in the ONE, TWO or OFF positions (but NOT the BOTH position) when charging. (I'm assuming they don't want their two five amp outputs connected together which the BOTH position would do.)

Assume I have the battery selector switch in the TWO position. If I have many active accessories (i.e. cabin lights, cockpit lights, etc), I could readily run down the number Two battery as five amps don't go very far.

Based on the factory information, I think I'm going to add a third battery, probably a very large one. Looking at the Guest manual, I'm considering two alternatives... a) putting the two existing identical original batteries in parallel and then using a single ACR to allocate the Honda's charging amps between the parallel battery set and the single large new battery; or b) use two ACRs and perhaps an additional battery selector switch to have three independent batteries.

I need to go back and reread some recent threads on ACRs and batteries. I'll also do some additional reading on ACRs/Battery Combiners. At this point I'm leaning toward option (a) because of it's simplicity.


Bill
Edgewater, MD

[Bill.Secure]

It appears that I may have passed along inaccurate information. Since receiving the factory phone call, I went out to the boat and attempted to find the unconnected 10 gauge red wire. An unconnected red wire was not to be found. Instead, what was found was that the sheath carrying the red-blue wire for the port battery also carries a red wire (is this THE red wire?) and two black wires. The red wire is crimped in along with the red-blue wire (and a brown wire from another source) into a single connector held onto the positive terminal battery with a wing nut. Both black wires coming from the sheath are connected to the negative terminal but with individual connectors.

This strongly implies that one of the chargers five amp outputs and its ten amp output are shorted out in apparent contradiction to the battery charger's manual. The Guest Charger manual states:

"2621A Connection Warnings: Do not connect output 3 (10 amp) of the 2621A in series or in parallel with output 1 or output 2 while charger is AC powered ON. Charge separate batteries only. While charger is AC powered on, battery switch must be set to “OFF”, “1”, or “2”, not “both”."

To attempt to prove this, I removed both the positive and negative wires from the port battery. Then, after turning off the battery charger and the battery selector switch, I removed the 10 amp and 5 amp (middle) fuses from the battery charger, tested them and ascertained they were OK. I put in the ten amp fuse, turned on the charger and got voltage between the three crimped wires and one of the two black wires (but not the other black wire). I then removed the ten amp fuse, replaced the five amp fuse and ran the test again. This time I got voltage between the three crimped reddish wires and the second black wire (but not the first). All this shows is that both the middle 5 amp and 10 amp charger circuits are providing a voltage but nothing about their current.

In summary, I'm becoming concerned as to what is going on. The wiring certainly seems different than the factory communicated and it appears in complete contradiction to the battery charger manual. Assuming my analysis is correct, I'm wondering if there are any current or future operability implications to the wiring as it appears to be. I've e-mailed the factory again.

Bill Moseley
Edgewater, MD

[mikeporterinmd]

When I did the math, I decided I wanted at least 20 amps charging on
the house bank (assumes refer. of some sort). 5/5/10 is not much.
Put a small inverter in the mix and you will never keep up. But, it's
lots of work and expense to put in a larger charger. Because I wanted
the charger in the cabin and the batteries in the stern, I had to run 6 gauge
wire...that was expensive. (Note: I ended up with a 30 amp charger
mostly because I like the XC3012 from Xantrex, and they do not make a
20 amp model - at least when I bought mine.)

Mike

[thataway]

Agree with Mike, The 5 5 10 is not much battery charger--I added a second battery charger which was 20 amps (In retrospect I should have gotten the 30 or 50 amp Xantex.)--My Tom Cat only came with a 5-5 Battery charger--enough for the starting batteries only.

As for the wires. The #10 wire will probably be OK for the 10 amp charger--but if you go to a 20-30 amp charger consider adding a #8 or #6 wire. You want to double check the wire. I prefer to disconnect both ends, and use a continuity meter (Resistance meter) to check each wire. This requires a long enough wire to connect the leads of the meter with the red wire you are checking.

The reason to isolate the batteries (which the "off" on the switch is to avoid putting both inputs of the battery charger combined--and limiting the amout of current available. I would wire each battery indificually to the output--If you continue with the 5 5 10 chager, then the starting battery to the "Start" Battery, the second 5 charger to an "electronics" battery (You will want an ACR for the electroncis and house batteries when you put in the larger house battery). I use a group 27 (which came with the boat--as my "normal" house--lights, pumps etc and it charges off one of the alternators (via ACR). I have a second house battery--which is two group 31 batteries in parallel--these are charged by the 20 amp charger and are used for both refigeration and the electroncis--and isolated from the starting battery by an ACR. If you add a 3rd battery bank (or single battery--some have used an 8 D)--you will want to have the ability to tie it in with the other batteries with a switch--as well as turn it off. Also be sure and put fuses or circuit breakers on the ends of each wire (within 7" of the battery terminal) and at the output of the charger.

[Sea Wolf]

I sent this PM to Bill after he copied me a letter written to the factory regarding the wiring in his boat where it appears one 5 amp and one 10 amp charging circuits have been wired in parallel. Thought some of you might like to see if my reasoning is sound.

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Bill-

Seems like you've got this figured out. One 5 amp and the 10 amp charging circuits are wired in parallel on the one battery.

I don't know how the three coils are set up in the charger's transformer, or what it is about the subsequent diodes and regulatory circuitry that would make it unwise to hook them together, but here's a guess.

Might just be that the regulatory circuitry in each circuit would sense the voltage being applied by the other circuit to charge the battery, then because of the high voltage, think that the battery is fully charged, and turn itself off. They might both be doing this, going on and off repetitively alternately.

This is why twin motors have to have separate batteries, because two alternators and regulators can't be hooked to the same battery without this conflict.

What I'd do is take a fuse out of one of the two circuits, so the other on can charge effectively, at least for now. Sooner or later, you'll have to re-do the wiring, of course.

Joe.

[Bill.Secure]

C-Dory never expected the wiring to be done other than as specified in my earlier post (the ten amp wire left unconnected). They told me that this piece of wiring is done by the dealer, not the factory because the dealer does the motor and batteries.

Guest responded to me (see below in italics) that the wiring was incorrect but that what I should do was connect both five amp circuits to the same battery.

Bill,
You are correct, the wiring from the charger is not correct, however correcting the wiring is easy. All you would need to do is to remove the 5 amp lead from the battery with the 10 amp lead and hooking it up to the battery with the 5 amp lead. That way you will have 10 amps going to each battery.
Regards,
Sue DeLelys
Guest Technical Support


This would give each battery a total of ten amps charging. I'm about to do this, probably this afternoon if it doesn't rain.

Another little "revelation" is that I discovered that the connections to the battery selector switch are reversed. According to the manual, the starboard battery is battery ONE and the port battery is battery TWO. I was going to set the connections back correctly and the realized I'm going to do a lot of heavy duty upgrading and rewiring and might as well save it for then.

I'll probably follow the thoughts in Bob Austin's earlier post on this thread, probably adding a Xantrex 50 amp charger, ACRs, etc..

Bill
Edgewater, MD

[mikeporterinmd]

Consider the 30 amp Xantrex. The 50 amp is a lot of charging, and you will
need to install wiring that can handle 50 amps. Wiring for 30 amps, 3%
voltage drop is expensive enough.


Mike

[thataway]

I would only consider the 50 amp charger if you are going to upgrade the house batteries--for example I have two group 31 AGM batteries, which would tolerate the output of a 50 amp charger, on one bank (refigerator/freezer and electronics). The other house bank with a single group 27 battery has a smaller 10 amp charger, and the house batteries have 5 amp charger each.