Electrical connection for Aquajet RV water pump.

[miles2go]

Will this work, wiring it like the schematic?

[Jriddle]

I found that I could not run my loads from my 100 amp converter for very long. I ended up putting a 12 volt battery between the converter and my loads. I'm not sure why the converter would end up shutting down but seems to work very well now.

John

[miles2go]

Thanks, sounds like a "buffer" battery is needed, hmmmm. Maybe someone can explain that?

[bevans6]

It depends on the equalizer.  I have one that is actually advertised as a voltage converter/equalizer (24v to 12 v, 12v to 24v, or equalizer, all in one), designed to do exactly what you want to do with no 12v batter.  The Vanner, on the other hand, must have a battery.  if you get in touch with the maker, or a manual, you may find more information.

Brian

[Jriddle]

My converter is a 100 amp  Vanner.

John

[James77MCI8]

You do not need a battery as long as your electrical load does not exceed the equalizers/converters ability to maintain it(electrical load) The battery kicks in when the demand is higher than the equalizer can supply. Some converters/equalizers are designed for a continuous output at a certain load. There is also the surge capacity that must be taken into account and is different from mfg. to mfg.

[miles2go]

The SurePower can be used as a converter as well as an equalizer, so I am ok there. How about the wiring though? Can I wire the Aquajet through the relay as depicted in the schematic I posted?

[Jriddle]

You do not need a battery as long as your electrical load does not exceed the equalizers/converters ability to maintain it(electrical load
My equalizer load was not ever over the 100 amps. I did some tests and the tests showed the battery bank to be unequal. When I put the battery on it works fine.

John

[James77MCI8]

key word is ability

[Sean]

Andrew,

Leaving aside the discussion of equalizers and how they should be wired, yes, the rest of the diagram looks fine.  A couple of notes:

• Make sure the relay is rated for the full load current of the pump.
• As you've shown it here, the pump can be turned on from any of three locations, but can only then be turned off at that same location.  You may want to rethink this.
• Unless it is part of the pump assembly already, I would move the fuse ahead of the relay and even the master switch.

With regard to equalizer wiring, I favor wiring the equalizer directly to the battery bank, then using the center tap to provide 12-volt power.  This lets you draw surge loads well above the equalizer capacity, but, more importantly, lets the equalizer do its job of, well, equalizing.

HTH,

-Sean
http://OurOdyssey.BlogSpot.com

[Len Silva]

If conserving electricity is an issue for you (lots of dry camping) then I would consider putting the relay coil after the pump pressure switch.  That would eliminate the small current draw of the relay being on even when the pump isn't running.

[Sean]

... I would consider putting the relay coil after the pump pressure switch.  ...

That would be a good idea, Len, but I don't think it's possible with the Aquajet.  There is a pressure switch with a pair of wires coming out, but they lead in to a circuit board inside the motor housing, which is a variable-speed demand modulator for the pump.  I've got the same thing with my Sensor VSD pumps.

FWIW, we don't ever turn our pumps off.  They have been energized now continuously for six years, with perhaps 30-60 days of "shutdown" while we went off on cruises or whatever.  So if it were me, I would not bother with the relay or the switches, other than a single switch at the main DC panel.

(For the curious, in that time our main fresh water pump has pumped approximately 25,000 gallons of water and has been energized for over 50,000 hours.  We just replaced the valve unit for the first time a couple weeks ago.)

-Sean
http://OurOdyssey.BlogSpot.com

[gumpy]

FWIW, we don't ever turn our pumps off.  They have been energized now continuously for six years, with perhaps 30-60 days of "shutdown" while we went off on cruises or whatever.  So if it were me, I would not bother with the relay or the switches, other than a single switch at the main DC panel.

I use the Aquajet, and I'm with Sean on this one. I do have an electronic relay system that allows me to use multiple switches, but in reality, I seldom turn off the pump. It's pretty much
on all the time. I did turn it off briefly this morning when the upper tanks ran dry and I turned it off to silence it while I went to switch the tanks. Even when the bus is sitting in the driveway
at home, the pump is usually turned on.

I use two 2-gallon pressure tanks in my system, which Sean does not use. I like it because the pumps run less frequently, but more vigorously. I realize it somewhat defeats the purpose of a
variable speed pump, but it works well for us. 

[miles2go]

Sean, Craig, Len, thank you all for your answers and input. You can skip my "dissertation" ;-) and go straight to the modified schematic below... then refer back to my ramblings if needed, thanks for taking the time to help because I am scrambling.

1) The pump specifications, which I lost but remember this, say it draws 6.5 amps but they recommend a 30 amp relay, for use with Intellitec systems? Well, I don't have Intellitec or any ideas about it.

The 15 amp fuse is part of the pigtail on the pump but I can install another fuse before the master cutoff switch if needed, although now I am not sure what amperage to use as the relay was going to be 30 amp? So I have a nice little 12 vdc 30 amp thermal switch circuit breaker I thought I would put before the master cutoff switch? But probably not needed now.

2) I never thought about turning it off from another location. I thought if one goes in the bathroom they would turn it on, and then off when finished in that location. Same with the kitchen or plumbing bay. But because of the posts by Sean and Craig,  there is some question in my mind now about needing to turn it off at all. Maybe a master cutoff, but basically it seems Sean and Craig leave the pump on all the time.

I was only putting the control switches in there because I thought if dry camping it would save battery power and stop the pump from running if pressure leaked down. Or at night to assure no noise. but I have a pressure tank too, no idea how it would work with the variable pressure pump. I had it before I bought a variable pressure pump and then I was following Craig's example and just thought it was a good idea.

3) The Equalizer is a SurePower 52210 24/12V 100 AMP. (Revision B. after the recall). I have it wired for use as a converter (I think) and I am in some doubt about that. It has 3 terminals. 24v. 12v. and ground. I have the 24v. terminal straight to the positive terminal of the house battery bank. The ground terminal goes to the opposite side of the shunt from the negative battery terminals of the house and start batteries. This is a shunt used for a Bogart Trimetric meter I have had for awhile and just now installed. The 12v. terminal will feed the 12v bus bar for 12v. loads.

What worries me now (as I learn a little more each day) is that on a previous thread I had learned to cross tie the start and house banks. I did this with a continuous duty relay I recycled from the original 4905 AC/Heat system (the condenser fan relay). You may remember I erroneously referred to #2 wire and was advised to use 4/0 cable, which I did.

Now I am worried that when the banks are cross tied when going down the road (so I may use the roof airs through the 4024 inverter) there is no isolation or equalization and the two OEM 8D's, or the house bank may suffer from over or undercharging from the 50DN. Also, in a situation where either bank is lower than the other there may be a high surge from high to low (natural equalization) that may cause damage when the cross tie is energized.

I thought I had it wired as you referred to here; "With regard to equalizer wiring, I favor wiring the equalizer directly to the battery bank, then using the center tap to provide 12-volt power.  This lets you draw surge loads well above the equalizer capacity, but, more importantly, lets the equalizer do its job of, well, equalizing." but now I am not so sure I have it wired how you mean. Could you explain drawing surge loads above it's capacity please?

Also you are right about the Aquajet having a variable speed demand scenario which defeats Len's good advice to conserve electricity. Which is what I, and all of us, are after to a point. Take my three switches on the pump as an example of conservation, which now seems moot, especially after Seans comment, "So if it were me, I would not bother with the relay or the switches, other than a single switch at the main DC panel."

Which brings me to a final conclusion that this learning exercise of mine, although not entirely futile, has brought me back full circle to wiring the pump directly to the Equalizer 12v terminal (through a 12v. bus bar in a DC panel) with only a fuse or circuit breaker (what amperage rating? to protect the wiring) followed by a master cutoff switch and leaving the 15 amp fuse at the pump pigtail, which the manufacturer put there for the pump. I can use 10 gauge wire as I have a lot of it (overkill I guess).

How would I wire the switches to be able to turn the pump on OR off from any of the three locations?

Here is the revised pump circuit along with how I have the Inverter, Equalizer, cross tie, batteries and shunt wired.

Thanks again.
Andrew

[Sean]

1) The pump specifications, which I lost but remember this, say it draws 6.5 amps but they recommend a 30 amp relay, for use with Intellitec systems? Well, I don't have Intellitec or any ideas about it.

Intellitec makes lots of stuff, so it's hard to know what they are talking about here.  But 30-amp is a common relay size, and it's possible whatever they are talking about is just designed to work that way.  If you aren't using any of Intellitec's parts, don't worry about this number; if the pump really draws 6.5 amps, I would fuse it at 10.

The 15 amp fuse is part of the pigtail on the pump but I can install another fuse before the master cutoff switch if needed, although now I am not sure what amperage to use as the relay was going to be 30 amp? So I have a nice little 12 vdc 30 amp thermal switch circuit breaker I thought I would put before the master cutoff switch? But probably not needed now.

The fuse in the pigtail is to protect the pump itself, whereas a fuse or circuit breaker back at the DC panel is to protect the wiring.  It would protect the pump, too, so if you use the same rating as what's already on the pump, then the one on the pump is redundant.  Lots of automotive component manufacturers put dedicated fuses in their pigtails because they assume the device will be installed on a much larger circuit shared with other items, and they don't want to leave it to chance (or trust the installer) that a properly rated fuse will be installed upstream.  If it were me, I would leave the one on the pigtail right where it is, but connect the pump (and all your other 12-volt loads) to a proper DC panel with both fusing and disconnect means for each DC circuit.

2) I never thought about turning it off from another location. ... I was only putting the control switches in there because I thought if dry camping it would save battery power and stop the pump from running if pressure leaked down. Or at night to assure no noise.

Our variable-speed pumps use almost no power at all when they are not running.  It is true that turning the pump off will ensure it uses no power at all, but for us the convenience of having household water pressure all the time, without having to think about it, is worth the minuscule sensor drain.  We never hear the pump come on in the middle of the night unless we have a leak someplace, and, in fact, the way I knew the check valve body was finally going (after six years and 50,000 gallons) was that the pump would sometimes come on at random times (for less than a second) and we had air in the lines.

If you will permit a slight digression here, we have three RainBird irrigation valves, some tees, and extra plumbing back to the fresh water tank from each of our three hot-water fixtures.  This lets us bring hot water all the way from the water heater to the fixtures without wasting a drop waiting for the water to get hot -- we open one of the valves and it sends that water back to the fresh tank.  We save about half a gallon of water this way every time we shower or wash dishes.  However, those sprinkler valves accumulate a buildup of calcium on their diaphragms over time from all the hard water one inevitably gets while traveling.

The calcium buildup eventually causes the diaphragms to leak slowly, and usually the first indication of this will be Louise poking me in the middle of the night to tell me she hears the dripping of the water back into the tank.  But she almost never hears the pump, and we don't notice any additional electric consumption when this happens.  When it does happen, this was one of the few times we would turn off the pump, however, I have since added stops just ahead of the sprinkler valves for when this happens.

The only other time we turn off the pump is when we run out of water, which is seldom.  But when it happens, you'll want the cut-off switch inside somewhere where you can get to it.  We have a single cut-off switch, and it's in the bathroom.  It's also directly in-line in the circuit from the DC panel to the pump, no relays involved, but our pumps are 24-volts so voltage drop was not a factor with the wire gauge we used.

3) The Equalizer is a SurePower 52210 24/12V 100 AMP. (Revision B. after the recall). I have it wired for use as a converter (I think) and I am in some doubt about that. It has 3 terminals. 24v. 12v. and ground. I have the 24v. terminal straight to the positive terminal of the house battery bank. The ground terminal goes to the opposite side of the shunt from the negative battery terminals of the house and start batteries. ... The 12v. terminal will feed the 12v bus bar for 12v. loads.
...
I thought I had it wired as you referred to here; "With regard to equalizer wiring, I favor wiring the equalizer directly to the battery bank, then using the center tap to provide 12-volt power.  This lets you draw surge loads well above the equalizer capacity, but, more importantly, lets the equalizer do its job of, well, equalizing." but now I am not so sure I have it wired how you mean. Could you explain drawing surge loads above it's capacity please?

OK, looking at your drawing, I must tell you to ignore my previous comment about this.  Your choice of 8v batteries renders the decision moot.  The only way you can use your Sure Power equalizer is as a straight converter, with the 24v post hooked to the positive of your 24v bank, and the 12v post supplying power to your 12vdc loads.  One consequence of this is that the total amount of 12v load you can run at once can not exceed the rated capacity of the Sure Power.

I'm sure you know that 8v batteries are uncommon.  More traditionally, RVs use either 6v or 12v batteries, and in either of those cases, 12 volts is available in the "middle" of a 24 volt battery bank.  It is common for the 12 volt load panel to be connected directly to this "center tap", and in this case, the equalizer serves to ensure the upper and lower halves of the battery bank see essentially the same amount of draw and charge.  In this case, because half the battery bank is available as a buffer, the 12-volt load can actually exceed the rated capacity of the equalizer for periods of time.  When the load drops below the equalizer's capacity again, then the equalizer will "make up" the difference over time by drawing from the upper half to replenish the lower half.

What worries me now (as I learn a little more each day) is that on a previous thread I had learned to cross tie the start and house banks. I did this with a continuous duty relay I recycled from the original 4905 AC/Heat system (the condenser fan relay). You may remember I erroneously referred to #2 wire and was advised to use 4/0 cable, which I did.

Now I am worried that when the banks are cross tied when going down the road (so I may use the roof airs through the 4024 inverter) there is no isolation or equalization and the two OEM 8D's, or the house bank may suffer from over or undercharging from the 50DN. Also, in a situation where either bank is lower than the other there may be a high surge from high to low (natural equalization) that may cause damage when the cross tie is energized.

With a solenoid (as opposed to an isolator) there is no danger of the 50DN under or overcharging either bank, so long as the regulator is set properly.  When the banks are cross-tied, the battery sense lead will see the aggregate combined voltage and excite the alternator accordingly.  If one bank is full and the other empty, charge will start to flow from the full bank to the empty bank as soon as the tie closes; the more depleted bank will accept more power from the alternator than the less depleted bank.

...
How would I wire the switches to be able to turn the pump on OR off from any of the three locations

For two locations, you'd need SPDT switches and wire the same way a household "three way switch" works.  For three or more locations, you'd need two such three-way switches and then an additional "four way switch" for each additional location.  This is just a DPDT switch that has been wired in an X configuration; Google "four way switch wiring" to see how three- and four-way switches are wired and work together.

Here is the revised pump circuit along with how I have the Inverter, Equalizer, cross tie, batteries and shunt wired.
...
This is a shunt used for a Bogart Trimetric meter I have had for awhile and just now installed.

The other comment I have on this diagram concerns the shunt.

Having both battery banks connected to the same shunt will not work.  You want the shunt only on the house side, not the chassis side.  If you also want to monitor the chassis batteries, you need a second shunt and a meter designed to work with two shunts (or two single-shunt meters).  So in this diagram, you want to move the negative cable from the chassis batteries off the "high" side of the shunt and back to the frame-ground side of the shunt.

HTH,

-Sean
http://OurOdyssey.BlogSpot.com