Cli-mate transformer controller 2.5A

A stepless temperature-driven controller with a copper coil, rated to 2.5 amps. For fan boxes heavier than the 1.5 A version can take.

How to work out which amp rating you need

This is the one choice you can get wrong with a controller, and one look at your fan prevents it.

Every fan box carries a rating plate. It states the power draw, in watts or in amps, sometimes both. If it only gives watts, divide by 230 to get amps: a 250 watt box draws roughly 1.1 amps.

Then you leave headroom, and that is the part that gets skipped.

A motor draws considerably more than its rated current on startup. That peak lasts only a moment, but it is real, and a controller chosen at exactly the rated current has to handle it every time. Allow roughly a third above your fan's stated current.

So a 1.1 amp box sits comfortably on the 1.5 A version. If you are around 1.7 or 1.8 amps, this 2.5 A is the right choice, even though 1.5 A looks just about sufficient on paper.

What happens if you choose too tight: at best the glass fuse blows and you are left without extraction. At worst the controller runs hot and fails early. One size up costs little and removes both risks.

Technical Specifications:

• Control: stepless, automatic on temperature in 5 stages
• Technology: transformer with copper coil
• Operation: 1 dial
• Rating: 2.5 A
• Protection: glass fuse
• Housing: splash-proof, with mounting brackets and hanging points

Frequently asked questions

My fan only states watts.
Divide the wattage by 230 for current in amps. A 400 watt box comes to about 1.7 amps.

Can I put two fans on one controller?
Only if their combined current stays well within 2.5 A, including headroom for startup.

Is a heavier controller worse for a small fan?
No. A controller supplies what the motor asks for. Choosing generously does no harm; choosing tight does.

The fuse blows regularly.
That is the sign your controller is undersized for your fan, or that something is wrong with the motor.