questions about p-tap power for camera and monitor

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Phil999

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questions about p-tap power for camera and monitor

PostSat Aug 28, 2021 1:06 am

battery: Anton Bauer Titon Base (3 p-tap outputs)
camera: Pocket 4k
cable to camera: p-tap to 2 pin from BMD DC cable set

I want to power the camera and an external monitor with the same Titon Base battery. A simple thing, but as I don’t have any experience doing this, it’s better to ask the professionals:

What is the exact procedure of connecting/disconnecting, and switching on/off? What are the things one has to avoid?
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Mark Foster

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Re: questions about p-tap power for camera and monitor

PostSat Aug 28, 2021 11:16 am

to prevent your HDMI port from being grilled, the following should be observed:

first plug ALL the POWER, and then the HDMI (or SDI for some models) connector
before you switched on the camera and the monitor

at the end, switch off camera and monitor and
unplug FIRST the HDMI (SDI), and at last the POWER connections.

if you change your batterie, switch off and UNPLUG the HDMI (SDI) cable!
after that, the same procedure (if you have also disconnected the T-tap (P-tap)
cMP 5.1 2x3,46/96GB/2x2TB SSD/4x4TB/7101A 4x2TB 970evo+/HP1344/BMD4k/RadeonVII
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Re: questions about p-tap power for camera and monitor

PostSat Aug 28, 2021 7:23 pm

hello,

I had already measured severe leakage voltage with BMD small swithing supplies (without earth) . When connecting devices with earth to devices without earth, inputs may serve as decharge path.

But in this case with same battery potential... Is there a thread or a link explaining origin of this breakdown ? Which process conduct to failure ?

thanks.
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Mark Foster

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Re: questions about p-tap power for camera and monitor

PostSat Aug 28, 2021 8:12 pm

if the plus pole makes contact first when the T-tap (or any) connector is plugged in,
but the minus pole does not, then the voltage can run through the shielding
of the HDMI (SDI) cable and destroy the control chip in the camera (overvoltage).

this condition occurs when the camera and the monitor are connected to the same battery.
and it does not have to be a V-mount battery, the same is true for NP-F adapters,
or if the monitor has a power output for the camera and it is connected there.

you will find also infos abaut this problem at arri or RED:

https://www.arri.com/service/search/en/ ... DI+Outputs

https://rencherindustries.com/blogs/tec ... ri-cameras


https://support.red.com/hc/en-us/articl ... DI-Outputs


so, it is not a BMD only problem


.
cMP 5.1 2x3,46/96GB/2x2TB SSD/4x4TB/7101A 4x2TB 970evo+/HP1344/BMD4k/RadeonVII
macOS 12.6.3
BMPCC 6k pro (7.9.1)
meike s35 cine 25mm, 35mm, 50mm, 75mm
resolve studio 18.1.4
mini panel
speed editor
desktop video 12.1
intensity pro 4k
atem extreme (8.6.1)
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Videobegin

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Re: questions about p-tap power for camera and monitor

PostSun Aug 29, 2021 6:09 am

thanks for this return.

In radio broadcasting we had specific outlets with earth pin longer then others. So when inserting plug, earth was always first connected. "Funny" to encounter again this behavour 40 years after !

I intend to supply camera studio and converter through a charger : theses informations comme at the right time.

have a nice day.
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Phil999

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Re: questions about p-tap power for camera and monitor

PostSun Aug 29, 2021 10:04 am

thank you very much Mark. Now I feel confident about the matter.

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