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Rectangular black charger with LCD screen and detachable clamps

BatteryJack inc.

BatteryJack inc. Tank On Board 12V Battery Charger Maintainer 3.8A 2-90Ah

SKU CH-X925-ET09B

Charges and maintains 6 V and 12 V lead-acid batteries from 2 to 90 Ah with a 3.8 A automatic output, LCD status display and full protection against reverse polarity, over-charge.

  • Charges 2 to 90Ah lead-acid batteries
  • LCD display shows charge status automatically
  • 8A output with multiple protection circuits
  • Switchable 6V and 12V output modes
  • Interchangeable clamps and ring terminals included

On-Board 12V Charger for Lead-Acid Batteries

The Tank On Board charger mounts permanently on a vehicle to maintain 12 V lead-acid batteries from 2 to 90 Ah. It supports wet, MF, AGM and GEL chemistries and includes an LCD display for status feedback. Automatic operation with full protection makes it suitable for boats, tractors and seasonal equipment.

Replaces Manual Trickle Chargers and Portable Units

A fixed on-board unit removes the need to carry a separate charger to the battery each time. The jump is worth it when the battery stays in the vehicle for weeks or months and you want automatic maintenance without repeated hook-up. Detachable leads let you switch between alligator clips and ring terminals for permanent or temporary connections.

Limited to 120 V AC Input and 3.8 A Maximum Output

The charger draws 120 V 60 Hz mains power, so it requires access to shore power or a generator. Maximum charging current is 3.8 A with a tolerance of ±10 %, and peak voltage reaches 14.4 V or 14.7 V depending on mode. Batteries larger than 90 Ah or systems needing faster bulk charging fall outside its design envelope.

Highlights

  • Charges 2 to 90Ah lead-acid batteries
  • LCD display shows charge status automatically
  • 8A output with multiple protection circuits
  • Switchable 6V and 12V output modes
  • Interchangeable clamps and ring terminals included

Specifications

No published specifications for this item yet.

Questions about this item

Does the Tank On Board charger mount with ring terminals or alligator clips?

The unit ships with detachable lead sets that include both pole clamps and ring terminals, so you can choose the mounting style that fits your battery.

Which selector setting matches a 12 V car battery on the LCD charger?

Choose the 12 V output and the car mode on the front panel; the charger then applies up to 3.8 A at 14.4 V or 14.7 V automatically.

When should the ring terminals or alligator clips be replaced on this maintainer?

Inspect the leads each season and swap them if the insulation is cracked, the clamps no longer grip tightly, or the ring terminals show corrosion.

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