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Recharge On The Run: The Lazarus System

Recharge On The Run: The Lazarus System

Storm's brewing. Light fades as seething black clouds roll over the treeline and across the lake. The trees bend in a gray mist. Rain. Heavy stinging rain running across the lake, mixing with spray whipped from the surface by the gale.

Time to go. You turn the key. Clickclickclick. Check the cables and try again. Clickclickclick. Lightning blinds you seconds before the deafening thunder clap.

Check the kill switch. It's off. Clean the battery terminals. Check the wiring.


What now? If you're a real Boy Scout you might have cables to jump the starting battery with a deep cycle. Might work. Might start right away. Might take awhile. If the deep cycles are depleted from running all day, starting might take a good long while.

What if we told you that with a 90 percent probability of being right, you'd never again have to limp ashore and make an emergency phone call because of a dead battery? Wait! We're not through. What if we told you as a bonus you can recharge trolling-motor batteries with the alternator on your outboard? And that's not all. What if you could just back your boat up to an outlet and plug it in for overnight charging-never lift another battery? Now what would you pay?

Power. We take it for granted until it's gone. When it's gone on the water, the day's over. But a few added cables and plug receptacles enable you to recharge deep cycles while you move from one fishing spot to the next. Or to recharge starting batteries with your deep cycles. Either operation can be achieved by plugging in a short jumper cable or throwing a switch.

Rigging for recharge is relatively simple and certainly cost effective. Keeping deep cycles charged adds years of service. Long trips away from external energy sources are less intimidating, and you'll notice a reduction in your electric bills. Rigging for recharge saves time; time is money; time is your life. More time to fish means more fish in the boat, too.

The system depends on having a large enough engine and a reliable battery monitoring system. The bigger the motor, the bigger the alternator; larger alternators generate more juice than smaller ones. The cutoff is around 25 horsepower but any motor with at least a 10-amp-hour alternator will suffice. Smaller motors lack the necessary amperage for running time to recharge multiple batteries.

The Lazarus System brings batteries back from the dead. It's a miracle.

Basic Recharge Systems

Jim Wentworth developed the system highlighted here to avoid battery failure on the water. The system employs three auxiliary plugins that connect all the batteries on the boat. Depending on which receptacles are used, the jumper cable opens a connection between the starting battery and one of the deep cycles. If all systems are off, electrical energy flows from the deep cycles to the cranking battery.


"The most important function of the system," Wentworth explains, "is to charge the cranking battery in an emergency. But the main by-product of the connection is the added ability to charge deep cycles when the engines running by simply plugging in the jumper cable."

Wentworth calls this his "hard-plug" or loop-charge system. "The connections are visible," Wentworth says. "The plugs are out in the open so you can see the status of the system. You know when you're charging. By using a jumper cable -- a hard-plug system -- no components can fail. No relays to crash, no switches to puke (burn out). The system's simple, self-contained, and reliable -- no fail."

Another by-product is the added availability of outlets for spotlights, stereos, coolers, aerators, battery chargers, and any other electrical extras.

Some companies are marketing chargers designed to be installed right in your boat. Most employ "smart" chargers -- chargers with computer chips that tell the charger when to slow down and when to go into a float mode, floating energy between the power source and the battery, neither charging nor discharging after reaching 100 percent. Back the boat into the garage, plug it in, and you're charging.

The system relies on a monitoring unit connected to all 3 batteries. Alternators can pump too much juice into deep cycles. To protect against overcharge and stay one step ahead of rundowns, install a monitor that measures both voltage and percent of charge with toggles to switch from battery to battery.

Wentworth says monitoring batteries on the water is important for a variety of reasons. "With larger engines, the charging output of the alternator is much higher," he explained. "Don't start charging until batteries are down at least 50 percent with engines of 100 hp or more. Recharge only when it's necessary."

To get an accurate reading with battery monitors, let the battery cool for at least 5 minutes after charging. Batteries should be completely discharged once or twice a season then immediately recharged. If left dead for more than 24 hours, a battery may never again be able to reach its original charging capacity.

Batteries that aren't completely discharged once in a while develop memory and lose some charging capacity. Otherwise, keeping a battery completely charged is much better than leaving it partially charged for a long time. That's where a built-in recharge system pays its own way.

Refined Recharge

Wentworth has refined the same basic system for larger boats. On bass boats and larger craft powered by 150 hp or more he employs a 70-amp relay. The relay system eliminates the need for plug-ins and jumper cables. To charge on the run, just throw a switch.

"It takes a 70-amp relay to handle the energy from a 25-amp alternator," Wentworth explains. "The relay allows for a pair of switches to open or cut the power going from the alternator to the deep cycles. With two switches, a master and a slave, you can charge one battery, two batteries, or all three at the same time."

With both switches on, three batteries charge when the engine is on. With the hard-plug system, only two batteries can be charged at a time. The relay system is keyed to the ignition switch. When the ignition is on, the relay takes over. When the ignition is off, the system closes access to the cranking battery to prevent accidentally leaving the main slave on, drawing down starting power with the trolling motor.

With both switches on, you draw off all three batteries to start the boat. This is great in an emergency, but don't be careless. Keep track of the switches to avoid drawing down the deep cycles before and during ignition.

Situation: You're on the move after running the trolling motor for 4 hours. Push a button, flip a couple toggles, and the monitor shows that your deep cycles are drawn down below 50 percent. Throw the master (run-charge) switch into the charge position, throw the main slave to the charging system into the on position, and you're running energy into all three batteries without leaving your seat or slowing down. Later you can choose to keep charging one or neither of the deep cycles. The cranking battery, of course, continues charging through the alternator when ever the engine's running.

"It's a sweet deal," Wentworth chuckles. "Doug Stange (In-Fisherman magazine's Editor In Chief) took his rig up to Lac Seul, Ontario, after I installed his recharge system. Other folks unscrewed battery cables and toted batteries from their boats into camp to attach to the main camp generator every night after dark, then spent another hour carrying batteries and hooking them up again each morning. Stange, meanwhile, used his trolling motor 16 hours a day for seven straight days without ever having to touch a battery."

With a 30-amp alternator, you can push your batteries back up by as much as 30 percent in one hour's running time according to In-Fisherman Editor Steve Quinn, who has the relay system in his bass boat. It's especially helpful on big water, where running time is high.

A tournament fisherman, Quinn considers the recharge system invaluable. "In the past, I had to reroute cables to jump my starting battery during competition, eating precious minutes from fishing time," Quinn said. "If it fails, you may miss the deadline for weigh-in. The recharge system is vital."

When running energy into the cranking battery from the deep cycles with either the relay or hard-plug system, Wentworth advises waiting 5 to 10 minutes before starting the engine. "That lets the batteries equalize and gives the cranking battery time to power up," he says.

Depending on the size of the system, the number of components, and the length and complexity of the wiring, rigging for recharge costs $150 to $250 when installed professionally. Or use the diagrams shown here to do it yourself. Remember to install 40-amp circuit breakers on all leads and to use the proper gauge wire in order to allow the system to carry as much juice as possible.

With a recharge system in place, you can forget breakdowns and concentrate on finding fish. What pleasure after all these years!

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