CLARK 8033336 CLARK FORKLIFT CONVERTER DC DC 5V MFR’S P / NO 140034 #1 12:24

The CLARK 8033336 DC-DC Converter is a vital auxiliary power supply component used in Clark electric forklifts and other material handling equipment. Its primary function is to convert the vehicle’s high DC battery voltage (either 36V or 48V) down to a stable, regulated 5V DC output.

This 5V power is essential for operating the forklift’s low-voltage control and sensory systems. It is a critical component for ensuring the reliable operation of the vehicle’s electronic brain.

Key Specifications from the Label

• OEM Brand: CLARK

• Clark Part Number: 8033336

• Component Type: DC-DC CONVERTER

• Input Voltage: Designed for the nominal voltage of a 36V or 48V battery system. (The actual input range is designed to handle the fluctuating voltage of a lead-acid or lithium battery under charge and discharge, e.g., from ~30V to 60V+).

• Output Voltage: A stable, regulated 5 Volts DC.

• Output Current: The “#1” likely indicates a specific amperage rating for the 5V output. This is typically a lower amperage, often in the range of 2-5 Amps, sufficient for powering control circuits but not for driving motors.

• Manufacturer’s Part Number: 140034 (This is likely the part number assigned by the original manufacturer who produced this converter for Clark).

Key Features and Functions

• Voltage Regulation: Provides a “clean,” stable 5V supply from a variable and often “noisy” battery voltage, which is crucial for the precise operation of sensitive electronics.

• Isolation: Typically provides electrical isolation between the high-voltage battery circuit and the low-voltage control circuit, protecting delicate components from voltage spikes and transients on the main power line.

• Protection Circuits: Often includes built-in protection against:

  • Input Under-Voltage: Prevents operation if the battery voltage drops too low, protecting the battery from deep discharge.

  • Input Over-Voltage: Protects the converter from voltage spikes.

  • Output Over-Current / Short-Circuit: Protects the converter and the connected control units if a fault occurs.

  • Over-Temperature: Shuts down if internal temperatures exceed safe limits.

• System Power: Supplies power to critical systems such as:

  • The Main System Controller (the vehicle’s computer)

  • Throttle Position Sensor (Accelerator pedal)

  • Operator Presence Sensor (Seat switch)

  • Dash Display / Warning Lights

  • Solenoid Coils in the hydraulic control valve

Common Applications

This converter is an integral part of the electrical system in many Clark electric forklifts. A failure of this unit will often result in a complete loss of operation, as the vehicle’s control system will have no power.

Important Notes for Replacement/Repair

1. Critical Function: This is not a motor controller. It is a low-voltage power supply. Without it, the forklift will not function.

2. Exact Replacement is Crucial: The part number (8033336) must be matched. Using an incorrect converter could result in incorrect voltage, insufficient current, or a lack of necessary protection features, which could damage expensive control units.

3. Diagnosis: Failure symptoms include:

   • Complete loss of power (no dash lights, no response to key switch)

   • Intermittent operation

   • Diagnostic trouble codes related to control unit communication or sensor faults.

4. Installation: This is typically a plug-and-play component, but it is essential to disconnect the main battery power before installation to prevent short circuits.

5. Core Value: This unit may have a core value and should be returned for a credit if exchanging for a rebuilt one.