More on the PID

[Patience]

Ozone bisquettes?   You may have stumbled onto a new flavor for Bradley to offer Arc, you may get rich!  Sorry about your stepper, did the motor burn?  I ran your idea by a guy who went to school for this sort of thing, and he said I'd be better off  hiring a high school student looking for a summer job as a full time damper turner, for those types of motors can get expensive?

Atleast you saved the beef!  Keep upright, and get back to us on the automatic damper turner thinger that may cost a lot for what it does, but thats not the point!

Have, Patience

[Arcs_n_Sparks]

The stepper was fine; I toasted the driver for it. Like an idiot, I didn't limit the supply current...   >:(

Got the stepper out of an old printer (that is where a lot of surplus steppers on the web come from). My goal is to not have any accessory that costs more than 25% of the Bradley.

Arcs_n_Sparks

[Patience]

Hope you figure the autovent out your next go!! 

I put my PID project together today minus the TC I have to wait a week for.  It fired up and it reads the max temp w/o the TC, but I played around with the buttons and you could hear the alarm relay click on and off as I changed the value.  I still havn't looked in the smoke generator to see how many amps the puck advance motor requires.  Do you know?

I did not use a heat sink, though I did smear some silver compound on the bottom of the SSR and mounted on the large aluminum plate that comes with the project box.  I remember somebody in a different post suggesting this and is seemed like a good idea.  Its a 25amp SSR and from what I can tell, nobody has a heat problem even with the smaller SSR.  I think it'll be OK. 

Concerning your stepper motor, what is the driver?  How would you tell it how far to move the damper?  THanks!

Patience

[outlander]

patience,,

  if you wire in a contact relay { same voltage as power to PID } you can run wires to the smoke generator useing some  ? bannana plugs ? { think thats what they were called } and bypass  the "on" switch in the gen. you will still have to plug in the smoke gen as usual , but then you can use the alarms on the PID to turn on and off the smoke.

gen with pugs to conect to PID




chris

[Arcs_n_Sparks]

Concerning your stepper motor, what is the driver?  How would you tell it how far to move the damper?  THanks!

The driver was a demo board from Microchip (PICDEM). Has on-board logic and FETs. Used to evaluate both brushed DC motor control and stepper motor control. The board has overcurrent protection, but my failure was hooking up a 13.8V supply to what was suppose to be a 12V max. input.

Most steppers go 7.5 degrees/step. With a toothed belt and appropriate gear on the vent, it is pretty easy to calculate the number of steps from full open to full close.

Arcs_n_Sparks