posted 05-25-2011 08:34 AM ET (US)        

The switch is the familiar two-battery distribution switch that allows the load to be switch to either battery. The voltage sensitive relay is a dual sense design. In this way it will combine the two batteries in parallel whenever either one of them is being charged.

701S Switch
http://www.bepmarine.com/home-mainmenu-8/product-321/701s-mini-selector-battery-switch

710-125A Dual Sense VSR
http://www.bepmarine.com/home-mainmenu-8/product-270/ dual-sense-voltage-sensitive-relay-125amp-vsr-

714 Cluster
http://www.bepmarine.com/home-mainmenu-8/product-273/ 714-100a-single-engine-two-battery-banks
http://www.bepmarine.com/media/product/pro4d2e2e961425a.pdf

posted 05-25-2011 11:18 AM ET (US)         

I considered both for my Montauk when adding a second battery to it.

The main difference between the two is [described incorrectly the difference because the comparison was being made to a different BEP product, not the one under discussion--jimh].

The BEP kit also has short (#6 I believe) wires preconnected to the VSR from the switches underneath the cluster. With the Blue Sea you must provide those leads yourself.

I choose the Blue Sea kit over the BEP offering for my Montauk primarily because the single switch design allows me to turn the boats electrical system on and off with one switch instead of two. [Actually, the BEP model 714 is a single switch. Again, there is some confusion in the comparison because the wrong BEP product is being compared--jimh]

The BEP design allows easier installation while the Blue Sea offers easier operation in my opinion.

posted 05-25-2011 11:56 AM ET (US)         

BEP's own literature discusses this behaivor:

"Q: Why does my VSR ‘chatter’?
A: Because the charging system is too small for the batteries and
this is not allowing the VSR to work properly. Instead, once the
starting battery has reached the right voltage and the house battery
is connected the systems voltage is ‘caving down’ below 2.7 volts
and the relay is automatically disconnecting. The voltage then rises,
the relay re-engages; then the voltage drops the relay disengages
and the ‘chattering’ sound is heard as the relay quickly switches in
and out. Refer to battery sizing chart on next page."

http://www.bepmarine.com/media/product/pro4c27c846d96d1.pdf

Blue Sea's ACR seems to be equipped with a pretty agressive Hysteresis ciruit to prevent chatter:

"Blue Sea Systems’ 120A SI ACR (7610) is programmed to prevent cycling when combining battery banks. It will remain closed and keep the battery banks combined usually long enough for the system voltage to recover. When two battery banks are combined, if the secondary battery bank draws down the system voltage, the 7610 will remain closed if the system voltage rises to at least 12.35V within ten seconds and at least 12.75V within 30 seconds. If the system voltage rises to these levels, the battery banks will remain combined. The 7610 recognizes rising voltage between 12.35V and 12.75V as a signal that charging is occuring even though the voltage is still below the normal drop out voltage of 12.75V."

http://bluesea.com/viewresource/527

posted 05-25-2011 01:51 PM ET (US)            

BEP literature explains their VSR hysteresis in their literature.

http://www.bepmarine.com/media/product/pro4c27c846d96d1.pdf

The OFF threshold (12.8-Volts) is lower than the ON threshold (13.7-Volts).

posted 05-25-2011 03:04 PM ET (US)         

This is contrast to the 716 which has 3 switches and allows house and engine circuits to be isolated without additional components. http://www.bepmarine.com/home-mainmenu-8/product-278/ 716-sq-100avsr-dual-battery-charging-cluster

Again the Blue Sea single switch does not flip flop between batteries, position 1 makes two independent connections for starting and house, position 2 combines both circuits. It is physically like the BEP 714 but functions more like the BEP 716.

As far as the hysteresis of the BEP VSR, it seems to only be voltage based not voltage AND time based like the Blue Sea.

This would still cause oscillation, cycling, or chatter in the scenario you described in the other thread where the VSR engages and the charger cannot supply the required current to keep the voltage above 12.8 volts. This is described in BEP's literature right after they describe their hysteresis: "A buzzerlike sound can be heard as the relay quickly switches in and out. Disengagement can occur at idle (low amps out due to slow speed of alternator) or if the house battery is at a low charge. An increase of the engine’s RPM will increase the alternator output and hold up
the voltage."

posted 05-25-2011 06:05 PM ET (US)            

The BEP model 714 eliminates a great deal of external wiring and external components needed with other devices. As I mentioned, the only additional component of the model 714 is a small-gauge wire which is run to the negative bus. Other than this there is no further complexity to the model 714 than there is to just a plain battery switch. In contrast, other battery management devices require a significant number of additional components, such as fuses, cables, connectors, terminals, and so on. Their cost will often be as great as the automatic relay device, and on an open boat it can be difficult to find a good place for all of those extra components.

The BEP model 714 seems to be very well suited for use on a small boat where a single engine and two batteries are employed.

posted 05-25-2011 06:50 PM ET (US)         

It also requires two #6 or larger wires from the positive leads on the switch to positive leads on the ACR. These #6 wires still exist in the BEP 714, they are simply installed at the factory, which does save some cost and installation time.

I am not sure why the BEP system does not require a small fuse on the negative lead like the Blue Sea does, as this is a potential path to negative from the high current battery leads through the VSR and a fire danger if that where to occur. Perhaps the have an internal one time use fuse or are very confident in their internal relay design and deem it unnecessary.

The negative lead with inline 10 amp fuse cost less than $10 at West Marine, I would recommend this be used even with the BEP kit.

posted 05-25-2011 08:32 PM ET (US)            

http://bluesea.com/viewresource/1388

posted 05-25-2011 10:10 PM ET (US)         

Of 5-6 fuses number that you say are required, two of them in the diagram are on optional circuits, the remote LED and ignition disable. How can fuses be required when those whole circuits are optional, circuits which by the way are not available on either BEP kit?

They also show two 150amp fuses on the house power circuit, this obviously has nothing to do with the ACR's presence, and simply their recommendation for house circuit fusing.

Whats left are the 3 fuses tied directly to the ACR operation, a 50amp on each positive lead and a 10amp on the negative. Obviously the 10amp fuse will blow and protect against a short to ground long before the 50amps, so what could the 50amp fuses possibly be for if the the ACR and switch next to each other and the ACR is tied to the switch posts instead of battery post as is the case with the BEP setup? Nothing, the 50amp fuses are recommend only if the leads going to the ACR travel some distance through the boat risking some other possible short to ground.

The only other possibility you could argue is the 50amp fuses protect against some sort of catastrophic battery short, which is true it might mitigate such an event from propagating to the other battery, in that case the BEP's fuseless design would also suffer from having no protection and suffer the same fate.

posted 05-26-2011 01:18 PM ET (US)         

I did not realize this topic should be limited to a single manufactures solution, perhaps the topic should read "BEP Marine Compact Battery Switch with Dual Sense VSR".

I honestly think there is very little more to be fleshed out, I know I would have found the information concentrated in this thread very useful when I was comparing BEP to Blue Sea's offerings and I am sorry you don't see it that way, but otherwise I have nothing to add.

posted 05-27-2011 08:55 AM ET (US)            

jharrell mentions:

"I choose the Blue Sea kit over the BEP offering for my Montauk primarily because the single switch design allows me to turn the boats electrical system on and off with one switch instead of two."

This decision would not apply to the BEP model 714 because the BEP model 714 is also a single switch. The comparison is not appropriate.

I don't have any objection to mention of similar products. I do find it confusing to introduce comparisons to different BEP switch assemblies other than the model 714.

posted 05-27-2011 02:52 PM ET (US)            

I agree that it's unclear if there is a battery combine function, and the photos and descriptions are indeed vague on that feature. If it does in fact have a combine function, the lack of house and start separation by battery becomes even less important in my mind.

posted 05-27-2011 08:32 PM ET (US)         

I personally have my engine tied to one side and my charger tied to the other, and either charging source engages the ACR confirming it's dual sense design.

The BEP 714 does not have a combine, and I assumed you realized this fact. This is obvious by it's 3 terminal design, the 714 simply redirects it's common terminal between the a and b terminals or both off. The switch simply allows you two switch between one battery or the other, while the second battery becomes disconnected.

This is why I said you could not isolate your house circuit and turn it off with a single switch using the 714 kit, you would instead have to tie house directly to the house battery bypassing the 714 and add a separate house switch. This would be similar to the 716 design.

posted 05-28-2011 08:34 AM ET (US)            

The BEP 714 appears to be the classic OFF-1-BOTH-2 type of switch, a style we are all familiar with.

There are only one or two models of Blue Sea Systems battery switch which are designed to keep the HOUSE and START loads separate. Most of the battery distribution switches Blue Sea Systems make do not keep the loads separate. Their model 5511e does this, and maybe one other variation, but most of their switches do not. If you want the specialized switch from Blue Sea Systems, you have to get the special model. Don't be mislead into thinking all Blue Sea Systems switches do this; they do not. Most work just like the BEP 701S.

If you want to maintain separation between HOUSE and START loads, BEP makes an assembly that does this which uses three switches. I find the BEP approach is actually more flexible and gives more control than is offered by the single switch design of Blue Sea Systems. For example, the BEP three-switch assembly can keep the HOUSE loads ON while the START loads are OFF, or vice-versa. I probably would have purchased the BEP switch assembly for my own application, but I got the Blue Sea Systems 5511e primarily because it would fit into existing holes the bulkhead where the old switch was mounted and I did not want to make more holes.

posted 05-30-2011 12:09 PM ET (US)         

Don't think that I am complaining. This site is an extremely valuable resource full of years high quality content easily searchable. This is no doubt because of jimh's moderation and attention to detail, so thank you.

Now back to the debate. I am not sure why the BEP 701s even has a combine position. Since it's single output can be switched between either battery, the combine seems to serve no purpose.

The Blue Sea 5511e provides all functions of the BEP 701s with the added benefit of keeping house and starting circuits isolated. It does all of this with one less switch position than the BEP.

When choosing a system for my Montauk one of my goals was running all electronics and jack plate off of the house battery, while keeping the starting dedicated only to the engine. This would not be possible with the BEP 714, which is why I only compared the Blue Sea with the BEP 716.

It is true the BEP 716 has some added flexibility with separate switches for house and starting and combine. I preferred the simplicity and ease of use of the single switch design. I already had a breaker on my house circuit which could be used to turn off house if needed.

posted 05-30-2011 12:43 PM ET (US)         

As for your suggestion that we need to get out and boat, I agree. I just got back in from a overnight at a cabin near the gulf only accessible by boat. All this talk of electronics and batteries and engines is really all for this in the end:

posted 05-30-2011 02:13 PM ET (US)            

http://continuouswave.com/whaler/reference/dualBattery.html

I have a cheap, single sensing ACR sitting unused on the shelf, because I do not know how it will behave when the only charging source is a float/maintenance charger, which is how I like to leave my Alert, when not in use. The single float charger is working the batteries, paralleled through the BOTH position. I don't _like_ storing the boat with the switch in other than OFF, but for the time being, BOTH is what I've got, if I want to float charge. Thankfully, both batteries are the same age and model and one is never much more discharged than the other.

I may eventually decide to go Jim's way or Jharrell's, or some other way. It remains to be seen. In the mean time, I have to go "manual" and try not to leave the battery switch in BOTH while anchored, beached, or drifting.

Do some boating on your time off, guys. I'm all the way across the country, on a Pittsburgh layover.

posted 05-30-2011 02:58 PM ET (US)            

There are other situations in which one might need to isolate one of the batteries from the electrical power distribution. For example, if one of the battery has been removed due to damage.

Switches with OFF-1-BOTH-2 connection arrangements like the BEP 701S are more flexible than the Blue Sea Systems switches (like the 5511e) that are being proposed as alternatives. With a Blue Sea Systems OFF-ON-COMBINE switch, a bad battery cannot be isolated. The remedy for that situation will be to temporarily disconnect the bad battery and carefully insulate the battery cable positive lead against accidental contact with anything else. This lack of flexibility is a significant drawback to the Blue Sea Systems OFF-ON-COMBINE switches which are being touted here.

The BEP battery distribution system with three switches which is intended for use in power distribution schemes were there is isolation between HOUSE loads and START loads is also more flexible than the Blue Sea Systems OFF-ON-COMBINE switch.

posted 05-30-2011 07:31 PM ET (US)            

For me a redundant battery is for back up in case the primary battery fails or otherwise has insufficient power to start my single engine.

Even when I had a cabin boat with an I/O V8 for power and heavier electrical loads redundancy was the purpose of the second battery.

I like what I'm reading about this new BEP product. You do not appear to be enamored but that does not mean many others are not.

I believe there is a place for both BEP and Blue Seas and the market place appears to agree.

posted 05-31-2011 07:14 AM ET (US)            

It came with a Blue Seas 6011 switch wired so that both the house and engine runs off of and charges the starboard battery while in the "ON" position. According to the Owners Manual you put it into the "Combine" position only if the starboard battery does not have enough charge to start the motor. The problem I have is the port battery does not charge unless you have the switch on the Combine setting.

I was thinking about the set up shown in the ezacdc.com site, it uses the larger (but similar) Blue Seas OFF-ON-COMBINE switch and the BEP VSR that a lot of people (including VOC) recommend. Not to fire up the debate again but is this the best of both setup (Blue-sea vs BEP)?

http://www.ezacdc.com/Scripts/prodView.asp?idproduct=155

http://www.ezacdc.com/prodimages/vsr_wiring.jpg

posted 05-31-2011 08:08 AM ET (US)            

http://i676.photobucket.com/albums/vv129/bluewaterpirate/ Two%20of%20a%20Kind%20Electronic%20and%20Fishing%20Upgrades/6-1. jpg?t=1306843587

http://i676.photobucket.com/albums/vv129/bluewaterpirate/ Two%20of%20a%20Kind%20Electronic%20and%20Fishing%20Upgrades/11-1. jpg?t=1306843639

posted 05-31-2011 10:13 AM ET (US)         

I wanted a dedicated house circuit on my Montauk so I could run the electronics/lights on my boat without worrying about discharging the starting battery. Probably one of the more common occurrences of starting problems.

The BEP 714 kit would still protect against this situation but one would have to manually switch over to the unused battery and hope it is still good and the VSR has been keeping it charged. With the Blue Sea setup it is fully hands off and since both batteries are regularly used, you know if they are in proper working order.

As far as combining the Blue Sea 5511e switch with the BEP VSR, there should be no problem doing so. In my opinion the Blue Sea ACR is superior to the BEP VSR, is has more advanced hysteresis to prevent chatter, extra optional leads for remote status led and ignition disconnect and seems more physically robust from my inspection of both. But I only have experience actually using the Blue Sea, it would interesting to hear what advantages either has from someone who has experience with both.

bluewaterpirate,

posted 05-31-2011 11:03 AM ET (US)            

I find it interesting that you have a dedicated battery for the house loads on a little Montauk. But it's your boat so good for you. Perhaps if I used my boat for all night fishing at anchor while using electric down riggers and blasting the waters with highly amped music I too would desire a dedicated house battery.

I kind of like redundancy. I have a second anchor and rode stored in the RPS which has never been used. I don't see any reason to use it if I don't need to. I do like to use the redundant battery every few weeks just because I'm [especially careful] and I want to "really know" it's up to par.

I can't wait for the rebuttal.

posted 05-31-2011 11:34 AM ET (US)            

I can also place my Emergency Parallel switch to ON and place both my start/house batteries to ON. In this configuration I can use both batteries to start my motor if the need ever arises.

I can monitor the the condition of my house battery one of two ways:

1. Using an external battery monitor or

2. Using one of my two chartplotters or my FF. I have power readouts that reflect just the house battery. Pretty simple.

I've never had to replace any of these devices I've installed for clients (Blue Sea Systems or BEP). My BEP is put to the test everytime I boat running to and from the fishing grounds offshore NC.

posted 05-31-2011 06:26 PM ET (US)         

So given the choice between two single switch solutions that cost nearly the same, I choose the one that does allow a true house circuit, and this is considered [obsessive behavior]?

Or is it [obsessive behavior] to have a second battery at all in my lowly Montauk?

bluewaterpirate,

From the wiring diagram of the BEP 716 it looks like turning off the starting switch and turning on emergency parallel would simply combine batteries for the house loads? Their diagram show batteries tied to the same lugs as the emergency parallel tie bars. Did you reverse the leads from their diagram and then move around the VSR leads to compensate?

This is the diagram I am talking about: http://www.bepmarine.com/media/product/pro4cd73148082df.pdf

posted 05-31-2011 07:47 PM ET (US)            

Please brush up on your reading skills. My post said nothing about you being [obsessively behaved]. It did say that I am [especially careful]. I don't think I said anything to infer that a Montauk is "lowly". I believe the word I used was "small". Matter of fact, my boat is a Montauk which is a step up from my previous little Dauntless 16 which also had dual AGM batteries.

Like I said, it's your boat and if you want to rig the electrical system in a particular way you should do so and good for you. That does not mean your opinion is any better than my opinion or anyone's opinion. Your boat--your way!!

Good luck.

posted 05-31-2011 08:44 PM ET (US)            

It is somewhat ironic, however, that the use of automatic combining relays or voltage sensitive relays to create automatic charging of the off-line battery (usually the HOUSE battery) can lead to a defeat of the principal purpose of the isolation of HOUSE and START. If the voltage of the START battery is quite high, it may cause the ACR or VSR to parallel the HOUSE battery to the START battery even when the engine is not running. Then, on engine start, the electronic devices on the HOUSE circuit may be affected because their battery is still in parallel with the START battery.

posted 06-01-2011 08:34 AM ET (US)            

http://cdn-2-service.phanfare.com/images/ 4892322_2160096_31023115_WebLarge_4/ Image-4892322-31023115-3-WebLarge_0_d24fdc94f039163c83cd8cad988a7611_1

http://cdn-2-service.phanfare.com/images/ 4892322_2160096_31023107_WebLarge_4/ Image-4892322-31023107-3-WebLarge_0_215779539cb5dd7522225e92edb49d6f_1

To it's prudent to have a dedicated start and house battery especially if you already have have two batteries.

Tom

posted 06-01-2011 08:36 AM ET (US)            

http://cdn-2-service.phanfare.com/images/ 4892322_2160096_31023107_WebLarge_4/ Image-4892322-31023107-3-WebLarge_0_215779539cb5dd7522225e92edb49d6f_1

posted 06-01-2011 12:04 PM ET (US)         

Again unless I am missing something, the emergency parallel is tied directly to the battery terminals A & C, this would make it impossible to isolate a bad battery and then use the emergency parallel switch to tie the good battery in.

You said: "As to isolating the batteries with the BEP 716. In the event my start battery goes bad I would turn the Emergency Parallel Switch to the ON position turn the start batery to OFF and switch the house battery to ON."