4 Channel 12V relay system issues.

I assume the issue is just with the schematics?

I understand a bit now why the jumper is there.  If the relays were 5V, then I only need to connect into VCC and the jump then shorts the VCC to the JD-VCC.  However since I have 12V relays, this jumper is worthless and should not be there.  I must connect 12V to the JD-VCC for the relays to function.

Not very intuitive at all.

The thing I need to figure out is my batter can get as low as 10V, will the relays still fire?  If not I need to get a 5V version.  The 12V was by accident.

Hi Joey, From my experience you will probably find that the 12 V relays will close at about 8 volts and release around 3 or 4 volts. If you have a variable voltage supply you can test this for yourself, just be careful to get the polarity correct so you are not shorting your power supply through the flyback diode.

John

These do not function at all at 5V nor 6.6V for if they did I would not of had any issues    It works well at 11.5.

Thanks for the info, I will give it a try and report back.

These do not function at all at 5V nor 6.6V for if they did I would not of had any issues    It works well at 11.5.

Thanks for the info, I will give it a try and report back.

These do not function at all at 5V nor 6.6V for if they did I would not of had any issues

Did you have the jumper ON at the time ....?

jw0752 is quite right they will likely still work at 8v.....

Mark

Yes the jumper was on.  Believe me I tried nearly everything except connecting to the JD-VCC.

What is JD anyways?

Hi Joey,

I have no idea what does it means JD but I am sure someone has and will answer soon. Instead I was thinking to the problem of the relay working at 12 VCC In this case you can use - I think you have - a separate VCC voltage to drive the relays, i.e. ULM2003 with obviously the common GND with the board. So when you enable the darlington with the low VCC the external 12VCC closes the circuit and "click" the relay. It's a bit complicated as you add one more component but you save the accidental relays board without the need of a replacement. Take in account that ULM2003 is sufficient as it should not drain too much power as it is only to switch the relay while the power is managed independently by the other side of the relay.

Let me know if you need a sample darlington usage schematics with arduino.

Enrico

balearicdynamics

Enrico

It's been covered here

http://www.element14.com/community/message/152954/l/re-4-channel-12v-relay-system-issues#152954

Sorry, I was milling and I have lost some episode of the series . Also ignoring that it was a question and not a discussion ...

Enrico.

What is JD anyways?

Jumper Dynamics .... who knows since it is Asian sourced it may be a mispell ....

It's likely that it wouldn't work at 6.6v.

The relays are intended for 12v operation, your lamps are designed for 12v operation, so at 11v I would be considering the battery is down beyond safe use.

Your change to LED's will give a lower operating voltage with similar brightness as LED's are linear.

Incandescent lamps are not...

It's easy to miss when the inbox only presents parts of the discussion.....

mcb1 wrote:

 

What is JD anyways?

Jumper Dynamics .... who knows since it is Asian sourced it may be a mispell ....

 

 

 

Its getting harder to find things that are not, they have flooded Ebay and Amazon.  They now stock things in the US so the source is from the US meaning its even harder to discern.  Some go to great lengths to forge logos etc.

I suppose using a reputable retailer is preferred.  I'll admit I do enjoy making a order to china and paying the $2 shipping and waiting a few weeks.  Its a good way to get cheap experimental items such as regulators and discrete components.  Its also hard to beat free 2 day shipping from Amazon.

However without proper support some things would never work such as this relay board.  I highly doubt I would have connected 12V to the JD-VCC pin, but maybe in desperation.

Everything in this project Is chinesed sourced except the lights I ordered. Today will be the day I test the wireless adapters so I guess I'll see if I am going to pay the price for my cheapness.

The Arduino Pro minis I am using a Chinese sourced, they are still nearly $3 but work perfectly and all pins are broken out unlike many other copies.  I do own several legitimate arduinos ordered from Spark Fun.  They just "feel" nicer.  the real pro minis I have I got on sale for $6.

I don't plan to order any more arduinos I plan to switch to a different platform going forward, probably ARM based though I really like the Parallax Propeller.