DC Brick Question

[excal2]

Hi All

 

just found your site today , I'm trying to construct an automated blinds controller, i was hoping to use the DC brick to control the blind, as the motor will just be on in forward and on in reverse.

 

At the moment I have the correct motor but am just operating it with on/off switch without a reverse.

 

I have a question , as I'm an OpenHab user, is it possible to send the forward/reverse commands to the DC brick from OpenHab?

 

Just wanted to check this before ordering , as otherwise it looks like the perfect solution.

 

one other question , if I had 4 of these motors , and all i wanted to control was forward/reverse and duration , what would be the best brick to use, i would have wires to all motors back to a central point.

 

Any help is very much appreciated

 

kind regards

 

Excal

[borg]

Yes, you can use a negative "switchOnVelocity": https://github.com/openhab/openhab/wiki/Tinkerforge-Binding#dc-brick

 

To control 4 motors you need 4 DC Bricks.

 

If you just want to switch them for a specified duration you could of course also use the Dual Relay Bricklet or the Solid State Relay Bricklet.

 

Do you know how much power your motors need and at which voltage?

[excal2]

thanks for the quick reply , 6V motors running at about 40mA.

Just for controlling blinds , open close so its quite simple use.

 

how far from the PC can the brick be? I have cat5 cabling to the motor at the moment and was hoping to use this to link the usb to the PC from the brick.

 

Is this possible?

 

Thanks in advance

Excal

[borg]

The USB specification has a max length of something like 2m, i don't think you will be able to make a long USB cable with your cat5 cabling.

 

You can however use the Ethernet Extension

 

For 6V/40mA motors you can also use the Industrial Quad Relay Bricklet, which is way more cost efficient for your use case.

 

So to control 4 blinds you would need Master Brick, Ethernet Extension, Industrial Quad Relay Bricklet and some kind of power supply (USB Power Supply, Step-Down Power Supply or Ethernet Extension with PoE). Than you can directly use your cat5 cable and connect it to your local network.

 

I think that would be the best solution .

[excal2]

Sounds good the only issue would be that I would lose the reverse/forward function on each blind ? Correct?

[borg]

Ah, i didn't think of that. I don't know the exact cabling of your blinds. Perhaps you can cable it in a way that you can use one Relay to drive forward and one to drive backward to get the functionality back (by switching between two relays in software).

[excal2]

Thanks for the help , might stick with the DC brick as then I can expand them with a light sensor bricklet , which may be useful,

 

instead of getting a masterbrick + ethernet + DC brick , I'm going to use the cat5 to extend the usb , once its powered it should be ok , as I've used that in the past with other USB devices.

 

Thanks for all the info.

 

excal