# Squirrel cage blower **URL:** \ **Category:** Uncategorized\ **Created:** [17 August 2021 00:26 UTC](https://forum.core-electronics.com.au/t/squirrel-cage-blower/11068 "2021-08-17T00:26:52Z")\ **Posts on this page:** 1\ **Showing post:** 7
**Author:** ![Robert93820](https://avatars.discourse-cdn.com/v4/letter/r/ac91a4/32.png) [@Robert93820](https://forum.core-electronics.com.au/u/Robert93820)\ **Post date:** [18 August 2021 03:14 UTC](https://forum.core-electronics.com.au/t/squirrel-cage-blower/11068/7 "2021-08-18T03:14:20Z")
Hi Lance > [@Lance166926](#): > > It’s powered by a 12v transformer Actually AD-DC Adaptor. Bit of a difference, “Transformer” implies AC output. I hope that bit of mains wire from the PID controller to the SSR is not carrying mains voltage. I think most SSRs are 3-30VDC operating voltage. You must have been lucky to be able to find a DC SSR. Most I have seen have been zero crossing switches and as DC does not get to zero will never switch > [@Lance166926](#): > > I found the plans on a UK BBQ You should ask where this guy found a pot with enough current capability to use as a speed control. Also if he is still using it. Might have fried by now. If you only want to slow it down a bit measure the current then calculate a resistor to drop the voltage to 9 or 10 volts or whatever you need A bit wasteful on power heating up a resistor but might be the way to go if you don’t want to have continuous control over speed. Don’t forget to calculate the resistor power requirement too, I will probably get quite hot. If you don’t know how to do this refer to Michael’s recent post and video here > [@New video by Michael; How To Use Ohm's Law In Electronics](https://forum.core-electronics.com.au/t/new-video-by-michael-how-to-use-ohms-law-in-electronics/11064/4): > > Hi Michael I vaguely remember that project. I seem to recall some constructors having trouble calibrating etc due to switch and other stray resistance. Switch resistance is mentioned in the article I notice. Strays of any flavour can play a significant and disruptive part in most things. I remember when I was working we had a 40kW HF transmitter which flatly refused to tune above about 20MHz. This was a new unit and when it was built the fitters had wired a range change switch with the wrong s… Cheers Bob --- _[View the full topic](https://forum.core-electronics.com.au/t/squirrel-cage-blower/11068)._