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I have 2 electric forklift experts giving me conflicting information and I'd like to clear up the issue. I acquired some 48 volt electric forklifts whose battery banks have a listed capacity of 1100ah @6 hour rate, and the chargers they came with require 3-phase wiring, which is not an available option in my area. I tried to shop for a compatible charger that can use a 240 volt power source and it's on this subject that the local experts disagree.
"Expert A" told me that his shop sells a 240 volt charger that will work. "Expert B" said his company doesn't offer such a charger because, while technically possible, it would be unethical to sell because its regular use would shorten the lives of the batteries excessively. Expert A says that his 240 volt charger wouldn't affect the longevity of the batteries. Who is correct? That charger and the batteries are very expensive and heavy so I don't want to make an uninformed decision. Any Clarification would be greatly appreciated.

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    \$\begingroup\$ There is no real logical connection between the number of input phases and the way the charger works. There is no reason why a good charger could not be designed to use 240VAC single-phase. Do you have the make and model of the charger? \$\endgroup\$ – mkeith Jan 27 '18 at 8:01
  • \$\begingroup\$ It depends on the technology used to convert AC to DC. If classic transformer rectifier, "A" 240Vac is terrible charge crest factors >100 worse , dissipation factor temperature rise in battery. SO it depends on the design \$\endgroup\$ – Sunnyskyguy EE75 Jan 27 '18 at 8:20
  • \$\begingroup\$ Without filtering, the single phrase charger will give significant more current ripple than the three-phase equivalent, but having designed lead-acid battery chargers for a living, I find the battery-heating-due-to-ripple-claim highly exaggerated. Get yourself a primary switched real battery charger with at least three stages which suits your mains limitations on the input and your battery size and voltage on the output. There are plenty widely available. Shopping recommends are off topic here though. \$\endgroup\$ – winny Jan 27 '18 at 10:21
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Without knowing the details of either charger, I can't make any real recommendation, but I wouldn't buy Expert B's charger since he says it is not suitable.

Howver, the charger you select should be "smart", and provide a "three stage" charging profile - bulk, absorbtion and float. Such a charger will not over-charge the battery, and should have a charge current capability suitable for the rating of the battery it will charge.

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The single phase 240V charger may make lots of 100Hz ripple .It may not make much ripple because filtering components may be included in the design .When a forklift battery is charged the forklift is parked and most importantly the battery is not drawing any current .This means that the charging current is always positive even when there is lots of ripple .Ripple is alleged to reduce lead acid battery life due to microcycling .When a lone battery is being charged like in the forklift application microcycling does not happen .So the single phase charger will not shorten battery life . Some people have said that sulplating is less likely with a bit of ripple .

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