Fork lift charger

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Fork lift charger, the blue/orange box toward the right of the photo. The electrical service is on the left.

Maker Nexus uses an Eagletronic ML2 charger, model SR2400, fork lift charger to charge its electric fork lift. The fork lift is powered by a 36 Volt battery located in a compartment below the operator's seat.

The charger is powered by a 208 Volt 30 Ampere circuit, through a wall mounted fused safety disconnect switch to the left of the charger. According to the charger's nameplate, the maximum input current is 27 Amperes. Output of the charger is 36 Volts DC, with up to 140 Amperes.

The charger's internal control circuitry is powered by 36 Volts DC. AC power goes through a contactor inside the charger. The contactor does not have power to close until the fork lift battery is connected.

Yellow and green indicator lights on the right side of the charger's control panel show the status of power to the charger. These two lights were added to the charger by Maker Nexus, and they operate independently of each other:

  • The yellow light indicates that 208 Volts AC is being supplied to the charger, whether or not the internal contactor is closed.
  • The green light indicates that the 36 Volt battery is connected, whether or not the charger is powered.

When both of these indicator lights are on, the charger operates automatically.


Charging the battery generates hydrogen gas, which can explode in concentrations of as little as 1%. Charging the fork lift battery requires ventilation of at least 90 cubic meters of air per hour.[1] The rollup door must always be open whenever the forklift is being charged. Never disconnect the charger until you have turned off the safety switch on the wall.

Charging the forklift

Normal connection between battery and fork lift
Connection between battery and charger
Fork lift being charged
  • Before you begin:
    • Wear safety glasses when working on batteries or electricity.
    • Open the rollup door, to prevent accumulation of hydrogen gas.
    • Verify that the handle on the disconnect switch next to the charger is down, in the off position.
    • Verify that no indicators are lighted on the charger's control panel.
  • Access the battery:
    • Press the release lever on the fork lift steering column, and move it forward.
    • Press the release lever on the control column, and move it forward.
    • Press the release button, and lift the seat and battery cover out of the way.
  • Check electrolyte levels in battery.
  • Connections:
    • Disconnect the battery from the fork lift, by pulling out the plug connecting the battery and fork lift.
    • Plug the cable from the battery into the plug on the battery charger.
  • Start charging:
    • A green light on the charger indicates that the charger is connected to the battery.
    • Lift the handle on the disconnect switch next to the charger.
    • A yellow light on the charger indicates that 208 Volts is being supplied to the charger.
    • Other lights on the charger indicate charging progress.

DIP switches

DIP switch settings
Photo of DIP switches

The illistration shows the purpose of four Duel Inline Package (DIP) switches on a circuit board inside the charger. The photo shows how the switches are actually set. Switches 1 and 2 are off, and switches 3 and 4 are on. These are the factory default settings.

Indicator lights

Two indicator lights were added to the front panel of the charger to show the status of power and fork lift connections.

The yellow light is one of two Linrose model B1050A3 120V ambler neon lights. Two such lights were wired in series to operate on 208V. The second yellow light is in inside the charger. They are wired directly to the 208V supplied to the charger.

The green light is a Linrose model B1091M5 24V LED wired in series with a 1.5k Ohm 2W resistor to the charger output cable, which connects to the fork lift.


  • Jennifer Taylor (December 29, 2014). Understanding OSHA's Battery Room Ventilation Requirements for Optimal Workplace Safety. Solus Group. Retrieved February 20, 2019.
  • External links