4QD motor controllers for battery use
Motor controllers Accessories Shopping cart Instruction manuals Specifications and features Questions answered Service and fault finding Wiring diagrams Application notes

Recent additions

Our latest Programmable controller: called the Prog-150, this uses digital technology and includes the programmer. Details are available.

Sales section

• The price list, for small quantity orders - if you know exactly the model you want.
• Trade and quantity discounts
• Motor speed controllers catalogue, information sheets and sales
• Accessories catalogue and sales
• Catalogues and Manuals for printing out. Also wiring diagrams.
• Guided Features Tour. If you are new to the subject, start here. Very simple, explains the basics you will need to choose motor and controller.
• Distributors, service centres and other addresses
• General conditions of trading and payment

Information section

• Some short questions and quick answers
  with pointers to more info.
• Our motor current calculator
  lets you put in vehicle weight, speed and performance and calculates how powerful your motors and controller need to be.
• Battery Motors and Controllers pages.
  Lots of information, written in a style that we hope you will find interesting and readable, to explain as simply as possible the background to designing and using electric power. Many people read this through from start to finish (possibly several times) but it is written in sections to answer specific points.
• Wiring diagrams

Service Section

• Service and fault finding area.
  • Fault finding
  • Service information
  • Modifications and upgrade information.
  • Technical information
  • Application notes.
• Returning equipment for repair.

Miscellaneous Section

• Contact Addresses for 4QD worldwide distributors, motors and other things.
• Electronic Circuits Our sister site, 4QD-TEC is a world resource of electronic circuits.

Large Site Warning

There is a lot of information in this site, which is one of three 4QD sites: if you are interested in the information on offer you will surely need to bookmark it for many return visits! The size of the site means it can get difficult to find things - especially if you do not know what the site contains!

The site is therefore divided into commonly used areas - but there are more not-so-common areas, so do keep reading!

• Contact If you wish to contact us.
• Home always takes you to this home page
• Search we have a link to a 4QD site Google search.

Page Information