MikroKopter - Forum » Electronics » Relais output to FC / SV4

Relais output to FC / SV4

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Hi all,

For a project I'm working on I need to trigger my cameras with a potentional free contact and I was thinking of this:
https://www.roboter-bausatz.de/34/1-kanal-relay-5v-/-230v

Can I connect this straight to the FC? The coil current is 15-20mA and I think the FC out can handle 100mA?
I have FC 2.5

I also need a potentional free change over contact, can I connect a RC switch like this to the servo output (servo 4 on SV4) on the FC?
http://www.robotmarketplace.com/products/0-BATTLSW1.html

Thanks a lot!

Best regards
Peter
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Think about this type of device:
photomos-relais

They can handle AC/DC, are well isolated and need control current of only a few mAs (for one LED of the optocoupler). No freewheeling diode is required as for the inductivity of a electro-mech. relais.
They are available in different versions (SMD and DIL) and for a higher price with a fabulous low output resistance, which means the current through the output can be high (not for the linked type, but there are similar devices with lower resistance!).

...have fun...
Michi
« Bearbeitet von michi1911 am 19.09.2016 13:30. »
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Hi Michi,

Thx for your replay and link :)

I really need relais contact output, I think this is a transistor/fet switching device..?

Best regards
Peter
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Antiserial Fets with opto controlled Fets....replacing each relais in the specd voltage/current range.
No mechanical bullshit...no burning contacts...!!!no huge inductor!!!
I use it for almost any low power switch when decoupling is required.
...have fun...
Michi
« Bearbeitet von michi1911 am 19.09.2016 20:36. »
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Thx Michi!

I know what you mean but I still want to work with this mechanical bullshit ;) and my question is if I can connect this to my FC :roll:

Best regards
Peter
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That depends on the inductivity of your relais.
I would not drive a relais coil directly from the switch outputs and a "freewheeling diode" is in any case a must. You may not believe what voltage level a inductivity can induce to its driver when it is switched off without a freewheeling diode :shock: :shock: :shock:
You should carefully think about a driver stage (e.g. an open collector Transistor or open drain FET) when you really want to use a mech. relais!!!

...have fun...
Michi
« Bearbeitet von michi1911 am 20.09.2016 21:59. »
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Hi Michi,

Thx for your replay and reminding about the induction.
The relais that I need will be a small, low induction one but I'm going to check for a driver stage as you suggested, I don't want to kill my output :shock:

Thx and best regards!
Peter

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