Written on the 6th June 2014
Hiya:
I have a beginners question about the correct installation and voltage supply for quads using OPTO esc´s installed on my quad with a APM 2.6
My new quad has come with OPTO esc´s and I need to provide them with power using and external UBEC …so far so good…but I am reading about removing J1 and connecting (the ubec) to the OUT bus, ect …and if I do that , with J1 removed I don´t see where the RX is going to receive power from ???. I don´t use the Power module cable for the APM yet , but I have a friend that is willing to lend it to me …eventually , meantime I am reading that if I use OPTO esc´s – and no power cable module - I need to use 2 UBECS ?? one for the OUT bus and another for the IN bus…and remove the J1…why can I not use only one UBEC connected to the OUT bus LEAVE J1 in place and connect a power carrying cable from the IN bus that will feed the RX from the same and only UBEC ???..I don´t see why I can not do that ??
I understand that with OPTO esc´s I will need to use all the 3 wires from the esc…+Vcc , ground and Signal to each of the esc´s….is that so ???..don´t they get they get their internal working voltage from the 3s batt ??? …do we need to provide to the OPTO escs “ external “ TTL working voltages ??
I don´t know if anybody will make sense of the potpourri above but I will appreciate any comments in this matter…meanwhile I am not risking BLOWING my precious and only one APM board…!!!
And yes…I have read “ dozens and dozens “ of site and pages …but none yet dedicated exclusively to the correct installation of UBEC for OPTO escs in an APM 2.6 without using the power module…???..maybe I am chasing a red hearing…???
Kind regards…
6th June 2014
Ramon Rios.
JP1 on APM is a jumper that links the output rails to the rest of the board. Normally there are two ways to power APM: either via the power module (which you don’t use) and which requires to remove JP1. Either via the output rail (no PM) and then you can leave JP1 on.
People tell you to connect a second UBEC when you remove JP1 because then there is a separation between the output rail and the rest of the board.
If you are using an opto ESC, make sure you connect both the black servo wire and the signal wire (white or yellow) to APM.
In any case you are advised to use a power module and JP1 off.
Hope this helps