0

Using 12 volt power supply to run both valve and Pro Trinket
Moderators: adafruit_support_bill, adafruit

Please be positive and constructive with your questions and comments.

Using 12 volt power supply to run both valve and Pro Trinket

by niklasobrian on Wed Jun 05, 2019 9:58 am

Hi,

I am trying to make a watering system for my garden and would like to have just 1 power suply. From my understanding you van run the 5v pro trinket on anything from 5V to 12V it using the BAT+ pin. However i can only get the trinket running with lower voltage power supplies. So i have 2 questions:

1. Can you run the Pro Trinket on 12 volts and if so do you have any idea why my adapter won't work? (picture attached)
2. Is it possible to split a 12 volt power supply to run both the Pro Trinket and the 12 volt water valve simultaneously?

As a side note I'm wondering if you have any tips on things I should do to prevent the risk of a fire?

Thank you.

Ps. I have never posted in the Adafruit forum so if I am posting my questions in the wrong place just let me know
Attachments
61853510_2256416587952421_3427177456014983168_n.jpg
61853510_2256416587952421_3427177456014983168_n.jpg (104.22 KiB) Viewed 118 times

niklasobrian
 
Posts: 1
Joined: Wed Jun 05, 2019 9:39 am

Re: Using 12 volt power supply to run both valve and Pro Tri

by adafruit_support_mike on Thu Jun 06, 2019 1:39 am

This is the right place to post questions about a Pro Trinket, so no worries there.

The BAT pin can accept input voltages up to 16V, so a 12V supply shouldn’t be any trouble. Double check your connections with a multimeter to make sure the positive and negative lines aren’t swapped, and to make sure power is actually getting to the Pro Trinket.

Connecting the PromTrinket to the same power supply as a solenoid could potentially cause some glitches. All electromechanical devices.. speakers, motors, relays, etc.. generate a lot of electrical noise in the wiring that carries power to them. That noise can cause problems for other circuits connected to the same wiring, especially digital circuits (which produce their own kind of noise).

To avoid problems, try not to use any shared wiring for the valve’s power and the Pro Trinket’s power. Ideally, the two current paths should only meet at the terminals of the power supply.

As for preventing fires, the best advice we can give is to make sure you don’t exceed the rated operating values for any of the components. To be extra sure, hire an electrician licensed to work in your area to review the system. They’ll have a career’s worth of “been there, seen it get weird” experience, and will know any legal issues relevant in your area. If you can get on “drop by at the end of the day when we can talk and have a beer” terms, you’ll have a resource of enormous value.

adafruit_support_mike
 
Posts: 58856
Joined: Thu Feb 11, 2010 2:51 pm

Please be positive and constructive with your questions and comments.