BATTERY DOCTORBattery Disconnect Switches

BATTERY DOCTOR 20128 Side Terminal Negative Battery Disconnect Switch, 12V

The BATTERY DOCTOR Battery Disconnect Switch is a side post knife blade switch with a negative polarity and a maximum voltage of 12V. It features copper contacts and is identified by manufacturer part number 20128.

SKU 3G-OTH-497587

Brand

BATTERY DOCTOR

Item

20128 Side Terminal Negative Battery Disconnect Switch, 12V

Part Number

20128

Local availability & support — Singapore

Local office: 20 Woodlands Link #09-05, Singapore 738733
Phone: +65 8878 8355
Delivery: Same-day or next-business-day delivery within Singapore for in-stock items; 7–14 days for factory-order parts from Europe.
Payment: Invoicing in SGD. PayNow, bank transfer, and corporate PO accepted.
Ships to: Singapore

Technical Specifications

BATTERY DOCTOR

Manufacturer Part Number

20128

Type

Side Terminal, Negative, 12V 

Polarity

Negative 

Maximum Voltage

12V

Contact Material

Copper 

Technical Documents

No technical documents available for this product.

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BATTERY DOCTOR Products

3G Electric (S) Pte. Ltd. — Singapore

Product Description

Frequently Asked Questions

What is the BATTERY DOCTOR Battery Disconnect Switch used for?

This side post knife blade switch disconnects the battery to prevent parasitic drain, secure equipment during storage, or enable emergency power cutoff. It is commonly used on vehicles, boats, RVs, and industrial machinery where a reliable 12V negative-side disconnect is required.

What are the specifications of the BATTERY DOCTOR Battery Disconnect Switch?

The BATTERY DOCTOR 20128 is a side terminal, negative polarity disconnect switch rated for 12V maximum. It features copper contacts for low resistance and a knife blade design for quick, positive disconnection. The switch is designed for side post battery terminals.

Where to buy the BATTERY DOCTOR Battery Disconnect Switch worldwide?

3G Electric supplies the BATTERY DOCTOR 20128 battery disconnect switch to customers worldwide. We handle full logistics, customs clearance, and delivery to your location. Contact us for a quote and lead time on this side post knife blade switch.

How to install the BATTERY DOCTOR Battery Disconnect Switch?

Disconnect the battery ground cable first. Mount the switch securely near the battery. Connect the negative battery cable to the switch terminal and the other switch terminal to the vehicle chassis ground. Ensure all connections are tight and corrosion-free. Always follow manufacturer instructions.

Used in

Common applications for BATTERY DOCTOR

Fleet maintenance — Battery Doctor corrosion inhibitor MPN 16204 applied to battery terminals on trucks and buses to prevent acid buildup.

Heavy equipment electrical systems — Battery Doctor toggle switch MPN 20561 used for on/off control of auxiliary lighting on construction machinery.

Vehicle panel mounting — Battery Doctor switch panel MPN 20591 used to mount indicator lights in truck cabs.

Marine battery systems — Battery Doctor corrosion inhibitor MPN 16201 applied to terminal connections to reduce corrosion in humid environments.

Industrial battery rooms — Battery Doctor switch panel MPN 20590 used to organize control switches for stationary battery banks.

Bus electrical maintenance — Battery Doctor toggle switch with guard MPN 20565 installed to prevent accidental activation of battery disconnect circuits.

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BATTERY DOCTOR Products

3G Electric supplies BATTERY DOCTOR battery disconnect switches. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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