Current Draw Estimate

I’m using a CM3+ based Hypno (PCB: Hypno CMV4) with the Smays hub, a Razer KIYO Pro webcam (750mA), and a Korg nanoKontrol2 (<100mA).

With this configuration, how can I estimate the total current draw of the USB hub (inclusive of the hypno)?

Ah yes! Time for everyone’s all time favorite electricity equation image! (oh and dont forget good ol KHDBDCM for those units)

Hypno CM3 takes about 300mA on 12v rail, the draw you mentioned is 850mA on the 5v rail.

To answer your question we would need to know: What voltage PSU are we trying to calculate current for? 12v Eurorack? 5v wall power brick?

Equations in the image below can help you convert either one way or the other to whatever voltage is your PSU to compare against your spec.

Hypno is powered off the 5V USB hub in this configuration. If 300mA @ 12V is a safe estimate, then sure, it scales to 720mA @ 5V.

720mA + 750mA + 100 mA = 1.57A @ 5V

I thought I read somewhere else on the forum that Hypno draws more current when using a camera input, is that true? Maybe not, just wanted to confirm.

Looks about right. (I see the confusion now, since the CM3 version is discontinued the power spec listed above is now only on the modular grid page at the moment)

The warnings about current draw where just me asking people to be aware of not putting too much current draw on their PSU with the USB webcam not because the Hypno itself takes significantly more power in this mode (technically decoding mp4s is more of a load on the CPU so even though I havent tested thats probably the software state that takes the most power on the Hypno end, the spec above has some margin of error so it shouldn’t exceed the rating).

You should be just fine with this config. FYI since you have a powered hub if that becomes an issue you can just connect another USB power source to the hub along with the Hypno’s power input.

It sounds like your glitching problems were immediate and rendered the setup unusable? Recently I used KIYO Pro with my CM3+ Hypno for about 10hrs in a live VJ setup and I didn’t find any glitching issues. Several notes:

  • I got the KIYO pro recently (Nov 2022); current tech specs say that H.264 compression is used for USB 2.0
  • I never messed with the Synapse configuration software. KIYO into Hypno, straight out of the box.
  • Hypno firmware is v2.2.3. Shape B was only doing low-frequency overlays for color/texture.

The power thread here was mainly to gauge if it’s safe to power my Hypno setup and a few other USB devices on one of these typical Amazon power strips, where there’s a current draw limit for the group of USB ports.

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