1987 MK 1 Electrical System Upgrade - Feedback Requested

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mainesail

#180
If I had a dime for every time I have read;

"Your alt will cut back in a few minutes anyway even with a high performance alternator."

Sadly this is a result of either;

A) Murdered sulfated batteries

B) A poorly set up & poorly installed "performance alternator"

It is not at all uncommon for me to measure -0.6V to -1.2V+ of drop between the alternator and battery banks even after someone has paid big bucks for a high performance alternator system and then installed it in a poor fashion which murders performance. Remember a 3% voltage drop at 14.4V results in 13.97V at the batteries HOWEVER this does not take into account any terminations, fuses, switches, busbars etc.. Sizing for 3% in the wire quite often nets you 4% to 5%+ as installed..

While one of my images was referenced I would urge everyone to read it and let it sink in. The drop in that example made HUGE differences in charging performance that would also translate into major health benefits for the battery bank.

Regulators & Voltage Sensing - Why?

These are the results and they are rather shocking and this only represents a 0.6V drop and I see far worse;

This was a race boat and light and fast was the game. As such the bank was designed to be cycled to approx 35% SOC as opposed to 50% most cruisers would do. The cost of the batteries was not the issue for this owner. Battery weight and getting as much energy back into them, in the shortest time, was the main goal. He chose TPPL AGM's (thin plate pure lead) for their ability to take a high charge current rates yet he was not happy with how long his batteries were staying in bulk.

With a .5C charge capability on-board (.5C = 50% of bank Ah capacity) and Odyssey TPPL AGM batteries he should have been doing better than he was. I ran his alternator in bulk charge and measured a .73V drop from the alternator end to the battery end. Not a good find on a boat demanding the utmost in fast charging.... I fixed this issue by addressing the placement of the voltage sensing wires and beefing up both the positive and negative alternator output wires.. Performance increased, and all was good..

For this article I took a brand new Odyssey PC2150 battery (Group 31 12V AGM), that I had just tested at 100.2Ah's of capacity at the 20 hour rate.. I then discharged the bank down to 11.85V at 77F and the 20 hour rate of 5A. This left the battery at 35% SOC or about 65% discharged. The battery was then recharged with an approx .7V drop at 50A. I set the charger for a 14.7V absorption voltage. The results are in the graph above. Click on the graph to make it larger.

Points to Ponder:

*In 1 hour of charging, at a .5C charge rate, the battery never exceeded 14.3V.

*At just 14.0V, measured at the battery terminal's, the charger began limiting voltage. When measured at the charger end, it was seeing 14.7V and it began holding the voltage steady.

*Once the voltage is held steady current tapers off and charging speed reductions are happening.

*Maximum bulk time was limited to 30 minutes at 50A, due to the voltage drop. This resulted in just 41.93 Ah's delivered to the battery in the 1 hour recharge period.

Voltage not sensed at battery:




Sensing voltage at battery:
*In 1 hour the charge source delivered 49.37 Ah's to the battery. This is an improvement of 7.44 Ah's in just a short 1 hour charge cycle. This equates to a percentage increase in charge performance of approx 17.7%, just by moving two small wires.

*Bulk charge at 50A increased by 20 minutes to a full 50 minutes of bulk charging. Remember this was a 100Ah battery charged at 50A or .5C for just 1 hour. It spent a full 50 minutes of that hour in bulk before attaining 14.7V a much healthier voltage point for these batteries to get to.

*The battery actually attained the absorption voltage set point of 14.7V. In a PSOC environment this is far healthier for the battery than stopping at 14.3V. Even getting to 14.7V for just 10 minutes is far healthier than ever even getting there and it can help limit some of the effects of sulfation, even in a short 1 hour recharge..

*In the previous timage, with no on battery voltage sensing, that battery would suffer performance issues considerably faster due to never even attaining the 14.7V target with daily 1 hour recharges.

Voltage sensed at battery terminals:




Proper voltage sensing directly impacts charging performance & battery health in the short-run / PSOC environment we abuse our batteries in..
-Maine Sail
Casco Bay, ME
Boat - CS-36T

https://marinehowto.com/

KWKloeber

Quote from: mainesail on January 13, 2016, 01:47:22 PM


I ran his alternator in bulk charge and measured a .73V drop from the alternator end to the battery end.

RC, Why?  Were the cables sized properly, bad connections, questionable terminations? In Jon's case, with his cables, running the numbers (theoretically) the wire drop is 0.20v. 

Ken
Twenty years from now you'll be more disappointed by the things you didn't do, than by the ones you did.
So throw off the bowlines.  Sail away from the safe harbor.  Catch the tradewinds in your sails.
Explore.  Dream.  Discover.   -Mark Twain

mainesail

#182
Quote from: KWKloeber on January 13, 2016, 02:16:57 PM
Quote from: mainesail on January 13, 2016, 01:47:22 PM


I ran his alternator in bulk charge and measured a .73V drop from the alternator end to the battery end.

RC, Why?  Were the cables sized properly, bad connections, questionable terminations? In Jon's case, with his cables, running the numbers (theoretically) the wire drop is 0.20v. 

Ken

Why? Real world.... The owner sized for 3% which is already a -0.44V drop at 14.7V, not ideal for a performance charring system without voltage sensing, but that 3% sizing is WIRE ONLY. People often forget that the charts for wire sizing ignore all the other things that add voltage drop. For most circuits 3% is fine but it is not adequate for performance charging system and it did not meet his design expectations for offshore racing. That is when I was called in... 

Real world also means that when the wires were finally run the length, according to the owner, "was a tad longer." The wire passed through multiple lugs/terminals, a fuse, switch, busbar etc. and each and every connection adds more voltage drop to the wire loss..

I don't know Jon's wire lengths but I do see approx 16 connection points on the negative side and approx 6 on the positive side as well as a fuse. I tend to use 0.00025Ω per connection point as the resistance. Each lug is; wire to lug as #1 and lug to XX point as #2. Two connection points per lug. This 0.00025Ω seems to bear out quite often. It would be really stellar to see a 1.37% voltage drop (-0.2V @ 14.6V) but as installed that rarely happens.

Let's run the numbers on just the connection points at 80A:

22 *Connection points at 0.00025 = 0.0055

80A X 0.0055 = -0.44V

*I am assuming the connections are clean, tight and not made with a dime store crimp tool...
-Maine Sail
Casco Bay, ME
Boat - CS-36T

https://marinehowto.com/

Jon W

That's what I was thinking I read, just wanted to be sure. Thanks Stu.

I count the 6 positive connection points, but only count 12 connection points on the negative. Where do you see the other 4? The best I've been able to capture is my current total circuit from alternator to house bank, through all the jumpers, and back to engine ground is 36.84 feet. If I've done this right (remember I'm new to all this) at 80A and 1 AWG cable resistance of .000124, I end up with .365 voltage drop (3.04% excluding connections).

I can't remember the exact brand name of the crimper I've borrowed, but think T&B was on the case. When the crimp is made, it stamps a number on the lug. Jon W.
Jon W.
s/v Della Jean
Hull #493, 1987 MK 1, M25XP, 35# Mantus, Std Rig
San Diego, Ca

J_Sail

Jon,
You wrote:
Quote from: Jon W on January 13, 2016, 07:08:09 AM
Question on the location for the positive sense wire for the Balmar MC-614H.

The manual says it can be connected to either the alternator output, the common post of the battery switch, or the positive post on the house bank battery being charged. It would be easier to connect to the alternator output, but recall someone saying the more accurate connection was the positive post on the house bank battery being charged. Is the house bank the better connection point? Thanks for the help.

Jon W.

To give the short answer in case everyone else's was too long a read for some:
IN YOUR DESIGN IT MUST GO TO THE HOUSE BANK.

I believe that's where your diagrams showed it.

The whole purpose of the remote sense wire to sense the voltage being delivered AT THE BATTERY. Anything short of that defeats the purpose, which is to compensate for the voltage drop on the charge cable at high amperage charge rates, where even 0.1v makes a difference. (MaineSail has thoroughly addressed this nicely)

On a separate note, if you have not already permanently installed your four main batteries, it would be nice to install some sort of built-up edge to the exit hole in the bottom of the battery box so that an acid spill won't drip down that hole. A surface mount plastic pipe flange would be great if you can find and mount one there that still allows all the cables thru. I don't recall what Noah eventually did, but he and I discussed it when he did his retro, so you may want to ask him. I it's too late, don't sweat it.

Jon W

I will run it to the HB like shown. Looks like the negative goes there as well, I didn't notice that until now. I have it connecting to the engine ground.

Noah and I talked about covering the holes in the bottom of the battery box. Thanks for the help. Jon W.
Jon W.
s/v Della Jean
Hull #493, 1987 MK 1, M25XP, 35# Mantus, Std Rig
San Diego, Ca

Jon W

Stu,
     I was searching on AC grounding and found this thread "Electrical Systems - Grounding for DC, AC, SSB and Lightning". It references a West Marine site and article, but when I click on the link it takes me to the WM website not the article. Is that article available? Thanks.

Jon W.
Jon W.
s/v Della Jean
Hull #493, 1987 MK 1, M25XP, 35# Mantus, Std Rig
San Diego, Ca

Jon W

Finally have the new master panel from Blue Sea panel. Come to find out the power connection for both bilge pump 1 and 2 is bussed together so I re-purposed the bilge pump 1 power to be the VHF. Also moved the Balmar Ext Reg negative to the HB battery #4 negative, added the Pronautic temp sense wire, the AC bus to connect the Pronautic case ground and a jumper from it to the DC negative busbar. Up to 56 wires now. Hopefully the attached is a much clearer graphic that you can zoom into to see details. As always thanks for the patience and help.   Jon W.
Jon W.
s/v Della Jean
Hull #493, 1987 MK 1, M25XP, 35# Mantus, Std Rig
San Diego, Ca

Stu Jackson

#188
Quote from: Jon W on January 14, 2016, 12:05:14 PM
Stu,
     I was searching on AC grounding and found this thread "Electrical Systems - Grounding for DC, AC, SSB and Lightning". It references a West Marine site and article, but when I click on the link it takes me to the WM website not the article. Is that article available? Thanks.

Jon W.

WM changed the link when they redid their website since that was posted here in 2008.  Here it is, I fixed the link, too, thanks.

http://www.westmarine.com/WestAdvisor/Marine-Grounding-Systems

The Advisors should be on everyone's bookmark list.
Stu Jackson, C34 IA Secretary, #224 1986, "Aquavite"  Cowichan Bay, BC  Maple Bay Marina  SR/FK, M25, Rocna 10 (22#) (NZ model)

"There is no problem so great that it can't be solved."

Jon W

Thanks Stu. Without a galvanic isolator before the panel does the AC ground bus still get connected to the DC negative bus back to engine or only with a galvanic isolator in the AC circuit? Jon W.
Jon W.
s/v Della Jean
Hull #493, 1987 MK 1, M25XP, 35# Mantus, Std Rig
San Diego, Ca

KWKloeber

Quote from: Jon W on January 14, 2016, 02:02:01 PM
Finally have the new master panel from Blue Sea panel. Come to find out the power connection for both bilge pump 1 and 2 is bussed together so I re-purposed the bilge pump 1 power to be the VHF. Also moved the Balmar Ext Reg negative to the HB battery #4 negative, added the Pronautic temp sense wire, the AC bus to connect the Pronautic case ground and a jumper from it to the DC negative busbar. Up to 56 wires now. Hopefully the attached is a much clearer graphic that you can zoom into to see details. As always thanks for the patience and help.   Jon W.

Jon

So do I see this right - VHF powered off your always-hot pos buss?  Why not off a breaker on the new panel?

kk
Twenty years from now you'll be more disappointed by the things you didn't do, than by the ones you did.
So throw off the bowlines.  Sail away from the safe harbor.  Catch the tradewinds in your sails.
Explore.  Dream.  Discover.   -Mark Twain

KWKloeber

Quote from: Jon W on January 14, 2016, 04:42:52 PM
Without a galvanic isolator before the panel does the AC ground bus still get connected to the DC negative bus back to engine or only with a galvanic isolator in the AC circuit? Jon W.


Jon

The ABYC standard is bond the AC ground to the DC negative, regardless. 
However, there is controversy about that.  Understand precisely what the result of that bonding does (or potentially could do) to your boat, and what the (potential) upside of doing that is.  Then make an informed decision whether to do that.

Related - you concentrated on the DC side - besides the SmartPlug are you making any changes to the AC side?  An ELCI (hopefully)?  I saw your shore/gen switch.  What's your genset?

kk
Twenty years from now you'll be more disappointed by the things you didn't do, than by the ones you did.
So throw off the bowlines.  Sail away from the safe harbor.  Catch the tradewinds in your sails.
Explore.  Dream.  Discover.   -Mark Twain

Jon W

I'm routing the VHF to the always on bus to minimize failure points so there is minimal risk to losing the radio.

What is ELCI? If it is the same as a GFCI I believe I have at least one. If not it will be added. No genset yet just a future option.

Jon W.
Jon W.
s/v Della Jean
Hull #493, 1987 MK 1, M25XP, 35# Mantus, Std Rig
San Diego, Ca

KWKloeber

Quote from: Jon W on January 14, 2016, 08:48:10 PM

What is ELCI? If it is the same as a GFCI I believe I have at least one. If not it will be added. No genset yet just a future option.

Jon W.

Jon

An Equipment Leakage Circuit Interrupter is essentially a "whole boat" RCD (residual current device) -- similar to a GFCI that's also an RCD (that protects typically a single circuit.)  i.e., the ELCI trips with leakage anywhere past the main breaker -- the GFCI trips with leakage only in the circuit behind the GFCI.   There's other specific differences, but that's the basic bottom line. 

The presence or absence of an ELCI is germane to the AC-DC bonding controversy.

Where's your master breaker?   In new builds, an ELCI main breaker is typically used in place of the former over-current-trip-only main breaker. 

kk
Twenty years from now you'll be more disappointed by the things you didn't do, than by the ones you did.
So throw off the bowlines.  Sail away from the safe harbor.  Catch the tradewinds in your sails.
Explore.  Dream.  Discover.   -Mark Twain

Jon W

The main breaker for the AC is on the master panel as an off plus 2 position rotary switch. Off, Shore, Gen.   Jon W.
Jon W.
s/v Della Jean
Hull #493, 1987 MK 1, M25XP, 35# Mantus, Std Rig
San Diego, Ca