DC Battery plant upgrade

Transcription

1 Newport 41 DC Battery plant upgrade We finished the battery plant upgrade on our N41 during 2004, and wanted to share how we used the info provided by many Newport owners. We replaced the two existing Group 27 marine wet cell batteries. Goal: Phase I Protect navigation instruments from voltage drops during starting. With the original design, the networked navigation instruments would get knocked off line or nighttime illumination turned off when the engine was started. Sometimes the GPS would go offline also. Seriously annoying when approaching harbor at night in fog. Later: Phase II We will be replacing the DC distribution panel and wiring. At that time the 1-Both-2-Off switch, which is being reused now, will be replaced with two On-Off switches. The new config 1x dedicated engine-starting battery 3x 100 Ah AGM (absorbed glass mat) batteries. Hellroaring Technologies Isolator-combiner I found wading through the (many) Hellroaring isolation configurations took some time, and would be happy to answer questions. Many of their other customers are trying to isolate the aux battery, while most of us on a sailboat are trying to isolate the starter battery.

2 Photo #1 It s really easy once you take time to read their various instructions. Also found the owner willing to talk me through the concepts that were giving me trouble at first. Check Engine starting bank Optima Group 31 AGM (yes it really fits in a Group 27 box!) blue top delivers 900 CCA (cold cranking amps). The heavy + red engine starter cable was removed completely from the 1- Both-2-Off switch and re-routed so that it connects only to the Blue Optima starting battery. The starter on the Universal 5432 diesel should draws 90 amps or less at 11.5 volts according to Torresen Marine Diesel Direct. In Photo #2, the small purple wire extends power only to the breaker for the electric fuel pump. The orange wire delivers charging voltage from the Hellroaring Isolatorcombiner whenever a charging voltage is present from any source. (That orange wire is less than 10 inches and you can see the other end on the large isolator-combiner terminal in Photo #3) Should we run the starter battery down, we hit the micro switch to make the Hellroaring manually combine banks, wait about 15 minutes for power to transfer and start the engine again. The micro switch was connected to the two small terminals after the photos were taken. Photo #2

3 Photo #3 Hellroaring Technologies solid state relay BIC 95150B is the battery isolator-combiner. It is mounted on the back wall of the battery compartment. I am unable to find ANY diode voltage drop in their SSR (solid state relay) controlled design. That s a major difference compared to other choices, and the SSR is non-sparking, no moving parts and their B model includes over -voltage protection for the SSR.) House bank Photo #4 3x AGM house batteries with a total of 300 Ah. Each battery is a group 27 size unit so it fit easily. For the house batteries we used the "BatteriesPlus" franchise stores private label AGM battery called EverOn. If I was willing to give up the stowage space, we could move the starter battery into the next compartment (by adding a separate battery box) and then include a fourth house battery for a total of 400 Ah. Battery banks set up in

4 parallel like this should have all batteries of the same age/condition. The specs are good. Each house battery delivers: C20 delivery of 100 Ah in a group 27 size package. The reserve time is 210 minutes per battery with a continuous 25 amp load. With more normal on-the-hook loads the reserve time is over 18 hours each. The EverOn lead-calcium battery weighs 71 pounds -- as much as the Lifeline AGM units at half the price. The tall golf cart batteries would not fit in our available space, so the typical Trojan or other 6v alternative was not practical. Because the entire DC panel will be replaced as our next major project, we elected to LEAVE the 1-Both-2-Off switch. The switch was re-labeled to read Auto-isolate and Off. The panel was opened, and the large red lead from 1 was routed to the + terminal on the house bank. The cable to 2 was left in place at the switch, but wrapped in silicone insulating tape and FASTENED out of sight at the back of the battery compartment. The orange wire on the right in Photo #4 delivers charging voltage from the alternator, while the red-yellow pair of wires delivers voltage from the SCR shore power charger. We cleaned up all the cable lengths (shorter) after this photo was taken. Added bracing, and also changed the old in-line fuse that someone had put on the negative side. Isolator-combiner The Hellroaring Technologies isolator is made in Montana. It is well made. The big current lugs are 100% tinned brass, no moving parts, epoxy potted, transient protected, w a 95 amp continuous and 150 amp intermittent rating. Its primary role is to transfer charging current to the starter battery after the house batteries are recharged. It also offers user selectable override to manually combine both banks for emergency starting.

5 Photo #5 The three small lugs in Photo #5 are the control points for the Hellroaring unit. The house battery GROUND gets a jumper to the small ground terminal (front left closest to the unit s label) which allows the unit to continuously watch for a charging current over 13.4 v in order to combine the batteries. The other two small terminals (center and far) are for a remote manual over-ride switch that includes an LED indicator that is illuminated when the banks are combined. Advantages 1. Optimized use of both starting and deep cycle battery types. 2. The house battery and loads will be automatically isolated from your starting battery. Electronic devices sensitive to voltage dropouts during starting will not be affected (unless manually combined during starting.) 3. Achieve full charge for both batteries. No diode voltage drop effect when on. Very low on resistance (less than ohm according to the mfg.) 4. Simple automatic operation. 5. Simple manual parallel combination via a remote microswitch. From a remote console, you can use very small wire running a long distance to switch the batteries in parallel. Cons If your starting battery is depleted, you cannot immediately crank with your house battery. However, you would able to transfer sufficient charge from the house

6 battery to the starting battery by manually combining them for at least 15 minutes. This is good practice for a deep cycle battery anyway. Hellroaring suggests that a longer 15 foot #8 AWG be used from the large Terminal C to the starting battery. This controls current transfer. Most importantly, while in automatic the starter battery will not fail due to house loads drawing power while at anchor. Charger I reused the existing Newmar 20 amp charger because it s an SCR-type that limits float voltage to 13.2 volts. The other alternative would be a three-stage Guest or BatteryTender model. It was moved to a removable mounting board on the inside aft face of the bottom of the navigation desk. Photo #6 We made a 17 x 8 epoxy-sealed plywood T that included two heavy stainless bolts. The T was attached with 5200 to the inside of the nav station. The charger base (visible in Photo #6) was also epoxy sealed and attaches with thumbscrews to the bolts on top of the T. This allows the charger to be unbolted and set on the cabin sole outside the nav station. Alternatives and pricing The other serious contenders for house batteries that fit in the existing space were: Interstate DCS-88HT (AGM wheelchair battery) MK Solar 8a24 Costco's private label deep cycle marine wet cell The semi-serious contenders for house batteries that would have required modification of the existing space were: Interstate DCS-100L (AGM wheelchair battery) MK Solar 8a31

7 Trojan-105 (not considered because of their taller shape) There was no serious contender to the Optima 31M starting battery. Suggestion for getting a good price... If you have a local neighborhood gas station where you have bought tires & gas for a long time., ask if they can order the Optima for you. It s an Interstate product. Costs: $785 That s $389 for house bank, $161 for starter battery, $165 for the Hellroaring Isolator-combiner and about $70 in Ancor boat cable and connectors. The remote control module is $43 from Hellroaring. Other good sources of info: Paul McQuillan s/v Walkabout