775 Connect from The Robot Space

775 Connect - Inline Adapter Kit for Anderson Powerpole Connectors Designed by The Robot Space

https://www.therobotspace.com/v/vspfiles/photos/trs-775C-2T.jpghttps://www.therobotspace.com/v/vspfiles/photos/trs-775C-3T.jpghttps://www.therobotspace.com/v/vspfiles/photos/trs-775C-4T.jpghttps://www.therobotspace.com/v/vspfiles/photos/trs-775C-5T.jpg

775 Connect Kit Details:

  • Multiple Clocking Positions - 8 positions at 45-degree increments (permanent once set)
  • Protective Terminal Shield - optimized to prevent electrical shortages
  • Air Ventilation Spacer - promotes airflow to maintain circulation into the motor
  • Black for superior performance
  • Rated for 45 Amps
  • Assembly Required

Available January 2018

Inspired by 775 Inline Powerpole Connector from Ozzy Boards (http://ozzyboards.com/775-inline-powerpole-connector/)

What prompted you to develop your own instead of becoming a reseller for Ozzyboards in the USA?

We liked the Ozzy Boards design but after looking at some of our older robots we found that we needed the terminals to be in different positions based on the motor mounting. So we wanted to add some additional features.

It looks like this would interfere with any sort of encoder that mounts to the back shaft such as an RS7. Do you have any plans to make a version that has an encoder or can support one being placed in it?

If you don’t mind, what weight of copper and what trace width?
Please and thanks!

These are good questions. I would also be curious as to the testing methodology used to arrive at the claim of “Rated for 45 Amps”.

And with that, does that mean if you stall the motor ever so slightly, the board is fried?

Why not just talk to Ozzy Boards and attempt to collaborate on creating a more improved design.

With all the talk of ethics recently, I can understand where this question is coming from. However, in this case, I think this product is simply meant to compete against the Ozzyboards product. The Robot Space thought that they could design and sell a product that would beat the Ozzyboards offering. Kind of sucks for Ozzyboards, but that is just part of a market.

If a company thinks their design is already better and improved, why would they collaborate with their competition?

Great looking product. I think that both this and Ozzyboards have a place in the FRC community. I think that the deciding factor on these boards is the cost of shipping. The Ozzyboard will likely work for most teams but this new board will provided versatility when needed.

With Ozzyboard just starting up in the electronics market, I can see them getting edged out fairly quickly if their design ideas are stolen like this. I suppose that’s the unfortunate nature of capitalism but it is reducing innovation.

I wasn’t aware of the Ozzyboard before this… both products look great, and I think they’re differentiated enough. The Ozzyboard is $4.99, this one is $7.75. This one expands on the number of mounting options, making it more versatile and explaining the increased price.

Honestly, I’d be fine with ordering a few of each, then using them as needed (and restocking). If the Ozzyboard works, use it. If the mounting situation makes the Ozzyboard orientation not work, then go with TRS. I think there’s room for both products.

A couple of months ago we had no COTS board for 775pro motor connectors, today we have two distinct products that each fill different needs in the market. We’ll see how much space there actually is in the market, but as Jon said I personally can see room for both.

@Bkeeneykid - We were going to make the 775 Connect compatible with the AM-3773 Encoder Kit. However, it added too much cost for such a small use case. Also, this would have added significant delays to the release of the product.

@phargo - The final boards will be 2 oz Copper. For our theoretical calculations we used the following assuming 50A with 1 oz Copper:

http://www.wolframalpha.com/input/?i=((1.6810%5E-8+ohm+meters)++(5.0810%5E-4+meters))+%2F+((3.55610%5E-5+meters)++(1.01610%5E-2+meters))++(50+amps)%5E2++(0.04+degrees+C+per+watt)

We will be doing more testing when the final boards arrive but we our initial empirical testing (1 oz prototype boards) with motors have shown very little temperature rise.

Please try that again using IPC-2221 criteria. Here is one calculator.

Did your initial empirical testing include stall?

To be clear, I am not endorsing Advanced Circuits!!

I have used their services in the past … I happened to turn them up first.
http://www.4pcb.com/trace-width-calculator.html

2 oz copper with a 10C rise at 50 Amps on an external layer - I assume you have a two layer solution … top and bottom! What temperature rise did you design for?

Trace length and width is a bit of a challenge - I guessed at 35 mm length as an average. The calculator recommends 33 mm trace width, which could easily be split on each side of the motor if top and bottom copper are both used.

This is why I was asking about your trace width.
Thanks for the information!

I think the ozzyboard offers encoder compatibility, whereas this offers increased mounting positions. Very similar but still different use cases. It’s not like they just took the ozzyboard and spray painted it red :rolleyes:

If I were designing a PCB like this, I would use a copper pour connected to thermals. According to the the Q & A section at the bottom of the page (at the link you provided):

QUESTION: I use “wagon wheels” or “spokes” when connecting to a ground plane to make it easier to solder to. The trace width calculator is telling me to make the “spokes” so wide that it defeats the purpose. What should I do?

ANSWER: The wagon wheels spokes are very short length traces and are heat sunk to the plane. The trace width calculator uses empirical formulas based on long traces with no special heat sinking. Generally, the wagon wheel spokes do not have to be anywhere near as wide as long traces. However, at this time, I don’t know of a good way to do calculations for wagon wheel spokes.

Is this the correct standard to apply to this design?

@Richard - Our empirical testing with our prototype boards (1oz Copper), we stalled a 775pro for 10 seconds with a current of 50 Amps using a B&K Precision (1693) Power Supply. The max temperature rise of the PCB was less than 20 degrees C.

After this test, we ran the motor normally with no load (after the smoke was released) and the PCB rapidly cooled down to less than 5 Degrees C above ambient. Therefore we feel that the 2 oz copper version of the board will be even better.

Hope this clears things up.