Using the Digital Charger (2010-2023)

Updated October 20, 2025 14:22

You don't give your batteries a day off — so your charger better be able to keep up. Our Digital on-board chargers are workhorse power plants that feature a microprocessor-based digital design to create a quick, safe charge, keeping you on the water all day, year after year.

*Note: the Digital Chargers have been discontinued.

Jump to:

Compatible Battery Types
Select a Charger Location
Mount the Charger
Output Cable Lengths
AC Power Cord
Connect the Batteries
Inline Fuse
Extension Cord AWG for Plugging in the Charger
Charging with a Portable Generator
LED Indicators
Serial Number Location
Dimensions
Manual
- Digital On-Board Charger
  Models MK 106D, MK 210D, MK 220D, MK 315D, MK 330D, MK 440D

Compatible Battery Types

Digital Chargers are able to charge the following battery types:

Flooded (12V 6 Cell)
AGM (12V 6 Cell)
Some 12V Lithium (LiFePO4)

Select a Charger Location

Never place charger above battery being charged; gases from battery will corrode and damage charger.
Never allow battery acid to drip on charger when reading electrolyte specific gravity or filling battery.
Do not operate charger in a closed-in area or restrict ventilation in any way.
Do not set a battery on top of charger.
Do not mount the charger below the waterline of the boat or directly adjacent to fuel tanks.
Each DC output cord is six feet long. Make sure that all DC output cords can reach the batteries and that the AC power cord can reach a power source. When using an extension cord, make the AC connection to the charger outside of the battery compartment as far away as practical to reduce the risk of a spark igniting gases in the compartment.
Do not shorten the DC output cords, as this can affect charger output. If the DC output cords are not long enough, they may be lengthened by splicing and soldering 12 AWG (minimum) wire. Each splice should be covered with dual wall adhesive-lined heat shrink tubing to protect the joint from corroding. The splice should be made between the fork in the output cable and the fuse holder. The fuse holder should always remain within 7” of the battery terminals. The maximum extension length is 15 feet. You may contact the Minn Kota Service Department with any questions.
Even though the Minn Kota charger is capable of operating in a high ambient temperature environment, a minimum of six inches of unobstructed area should be allowed on all sides of the unit for proper air circulation and cooling. Proper cooling and circulation will allow the charger to operate at peak efficiency.

Mount the Charger

Due to the weight of the charger and the impact that boats routinely endure, take the time to securely mount the charger to prevent damage. Mounting with nuts, bolts and washers is preferable to mounting with screws.

Use the largest diameter bolts possible and use all four mounting holes.
After marking the locations, set the charger aside and drill the holes.
Apply a marine grade silicone sealant in each of the drilled holes to create a waterproof seal.
Then secure the charger in place using the mounting hardware.

Output Cable Lengths

Each DC output cord is six feet long. Do not shorten the DC output cords, as this can affect charger output. If the DC output cords are not long enough, they may be lengthened. The maximum extension length is 15 feet. To lengthen the DC output cords:

Use the Battery Charger Extension Cable MK-EC-15. The cable features WAGO® Wall-Nut™ quick connectors (UL listed), and fused (30 amp) positive and negative leads. You will need 1 extension cable per bank that needs a longer output cord to reach the battery(ies)
Click here for purchase options for the Battery Charger Extension Cable MK-EC-15, item number 1820089
Splice and solder 12 AWG (minimum) wire. Each splice should be covered with dual wall adhesive-lined heat shrink tubing to protect the joint from corroding. The splice should be made between the fork in the output cable and the fuse holder. The fuse holder should always remain within 7” of the battery terminals.

AC Power Cord

The power cord from the charger to the AC power, which plugs into your wall outlet, is six feet long.

Connecting Batteries

Each Output Bank is independent and isolated from one another and the AC Input. The Minn Kota charger can charge independent batteries or combinations of batteries hooked in series or parallel without disconnecting the batteries from any switches or Jump Wires joining the batteries.

Always ensure the charger is unplugged before connecting the batteries.
If you notice sparks when plugging in the charger, immediately unplug it and inspect the battery connections to confirm they are secure and properly attached.

Inline Fuse

Each output cord has inline fuses on the RED and BLACK leads located near the ring terminals. These fuses serve as protection from surges and short circuits caused by a damaged charger output cable. If a fuse blows, replace it with a 30 amp ATC 32V automotive fuse. Improper battery connections will normally not cause a fuse to blow since this is handled by the internal circuitry of the charger.

Extension Cord AWG for Plugging in the Charger

An extension cord should not be used unless absolutely necessary. Use of improper extension cord could result in a risk of fire and electric shock. If an extension cord must be used, make sure:

That pins on plug of extension cord are the same number, size and shape as those of plug on charger.
That extension cord is properly wired and in good electrical condition.
That wire size is large enough for ac ampere rating of charger as specified in table.

Extension cord ratings vary by the Minn Kota Charger model. Please refer to the chart below to find the extension cord that will work best with your model charger.

Charge with a Portable Generator

Careful selection should be used when deciding on a portable generator for electronics. There are 2 important factors that must be considered:

Output power:
Generators are marketed in output wattage. This wattage must be higher than the power required by the battery charger.
Output type:
Minn Kota chargers require clean output power from the generator to prevent permanent damage. The generator must replicate the power from a standard AC outlet in your home (clean sine wave output).
Safe for use with electrical equipment:
The generator must be safe to use with electrical equipment to prevent damage.

Below are the wattage requirements in order to power each charger type:

DIGITAL CHARGERS
- MK 106D -100W
- MK 210D -200W
- MK 220D -470W
- MK 315D -270W
- MK 330D -500W
- MK 440D -620W

LED Indicators

Each bank has the following LEDs:

RED LED indicates an issue.
- A solid RED LED indicates there is an issue with the battery connection.
- A flashing RED LED indicates an error (see the troubleshooting below).
YELLOW LED indicates the progress of charging.
- A flashing YELLOW LED indicates the battery is in the Bulk Charging stage.
- A solid YELLOW LED indicates the battery is in the Absorption Charging stage.
GREEN LED indicates the battery is fully charged.
- A flashing Green LED indicates the battery is fully charged, in Maintenance Mode and is ready to use.
- A solid Green LED indicates the battery is fully charged, in Long Term Maintenance Mode and is ready to use.