ISOBOB

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Re: ISOBOB

Postby ger21 » Sun Nov 13, 2016 11:53 pm

If I buy from Ebay, it's in USD, so no currency conversion. And with PayPal Credit, I have 6 months to pay, so only $30/month. :D

I might order one this week.
The manual is a bit weak, but it's just a bob, after all.
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Re: ISOBOB

Postby cncdrive » Mon Nov 14, 2016 12:32 am

ger21 wrote:The biggest issue here is the lack of quality breakout boards.
There are no high quality 24V I/O breakout boards available.


Well, our HDBB2 breakout board can do that on the 5 extra outputs, the outputs are not fast though, cut frequency is about 20kHz,
which is perfectly fine for driving relays. There are opto isolators driving N-FETs with the drains wired out.
They can drive upto 50V (absolute max. rating) and 1Amp.
We mostly drive 12VDC and 24VDC relays with them.

I'm surprised though if there are really no BOBs on the market which has optos and N-FETs or NPNs on the outputs with high enough voltage rating to handle 24Volts?!
Honestly I thought the market is flooded with this kind of boards this is why we never bothered to design one, except the HDBB2 which we designed about 6-7years ago when there were no cheap chinese bobs on the market or at least the market was not flooded with them.
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Re: ISOBOB

Postby A_Camera » Mon Nov 14, 2016 10:00 am

Robertspark wrote:http://www.cnc4youstore.com/cnc-breakout-boards/interface-boards/

Not cheap though.... I can vouch for them on quality.

Given the number of ports and pins on a uc300 I'd suggest a stacked modular board arrangement though... With stuff like a common enable and fault connection for each drive (leadshine am882... Plus others), that way modular replacement under failure plus compact etc.

Had a quick look... No, not cheap and I don't like that they are using sockets for those three chips. Could only read one of them 74HC245 which is a tranciver/buffer and I don't understand the reason for sockets. Why DIL chips at all? That makes it look so 80's or DIY design that for this reason I would not buy them. They can be very good functionally, but in my experience DIL sockets are a huge source of problems in general and especially in equipment which can be installed in places with high vibration and other mechanical or electrical disturbance. If I'd buy it I'd replace all the sockets immediately.
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Re: ISOBOB

Postby A_Camera » Mon Nov 14, 2016 10:05 am

ger21 wrote:The biggest issue here is the lack of quality breakout boards.
There are no high quality 24V I/O breakout boards available.


How about a breakout board similar to the ISOBOB that connects to the UC300ETH motherboard.
Or several single port boards, so that you have a system similar to CS Labs.
Maybe a 5V output board for motors. A 24V input board for home, limits and control buttons. And a 24V output board to drive relays.

As Terry said, if you could supply a complete setup, you'd be way ahead of the competition.


Yes, I support the idea of a kit as option, or even a separate board which the UC300 can be plugged into. ...at the same time I know that hardware development is very expensive, so it must be sold in pretty high volumes to make it feasible and worth while, so a market research is necessary otherwise it can cost CNC Drive far too much and will only generate losses.
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Re: ISOBOB

Postby cncdrive » Mon Nov 14, 2016 2:27 pm

Robertspark wrote:http://www.cnc4youstore.com/cnc-breakout-boards/interface-boards/


What I don't like on these boards for first sight is the builtin relays.
I would never build the relays on the board, because a machanical relay always have a lower lifetime than the other electronics which has no moving parts,
so sooner or later, but the relays will fail, the spring will break or the contactors will oxidate, so you will then have to find the same type of relay to replace it
and will have to unmount the board from your control box and do soldering.
How we doing this in our installations is we have only the NPN switches on the BOB and the relays are industrial ones in sockets connected to the relay drivers on the BOB,
so if the relay fails it can be popped out from the socket in a second and can be replaced with a new one.
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Re: ISOBOB

Postby ger21 » Mon Nov 14, 2016 3:18 pm

Regardless of the issues, I think I will try this board.
It won't work in my M44 motherboard, though, so I'll order a 5LPT motherboard from Arturo.
Gerry
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Re: ISOBOB

Postby Robertspark » Mon Nov 14, 2016 3:59 pm

I have removed some and added a few optoisolators as I needed some high speed low current outputs.

Sometimes you need dry contacts (like plasma torch fire interface), plus maybe higher voltage switching without any leakage.

We all want and see something different, I just listed it as Gerry asked about 24v bob options. That is consumer choice. The tristate tranceiver allows for charge pump interface.... Ok doesn't need to be bidirectional in their application, but it could be used for bidirectional LPT port switching
...
Remember the primary market for them is warp9 smooth steppers .... Not uccnc
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Re: ISOBOB

Postby shad » Mon Nov 14, 2016 8:03 pm

A_Camera wrote:Had a quick look... No, not cheap and I don't like that they are using sockets for those three chips.

Just from my experience.. This three chips are the differential line drivers 26LS31 from Texas Instrument. It's works perfect and has hi immunity to the RF noise (this is very important for example for plasma cutting).
Sometimes, users can make the wrong connection and chip will be damaged. I think therefore they installed chips in sockets for quick replacement.
I am use this chips too in the pulse/direction interface of the Neuron controllers in the SO16 package (no replaceable) but have special hi speed protection from wrong connection, over current and HI voltage spikes on the lines wires and it solves all problems.
-- Andrew
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UC300ETH-5LPT
NEURON Lite THC
http://neuroncnc.com/
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Re: ISOBOB

Postby Robertspark » Mon Nov 14, 2016 8:06 pm

Thanks Andrew, I learnt something there
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Re: ISOBOB

Postby A_Camera » Tue Nov 15, 2016 9:13 am

shad wrote:
A_Camera wrote:Had a quick look... No, not cheap and I don't like that they are using sockets for those three chips.

Just from my experience.. This three chips are the differential line drivers 26LS31 from Texas Instrument. It's works perfect and has hi immunity to the RF noise (this is very important for example for plasma cutting).
Sometimes, users can make the wrong connection and chip will be damaged. I think therefore they installed chips in sockets for quick replacement.
I am use this chips too in the pulse/direction interface of the Neuron controllers in the SO16 package (no replaceable) but have special hi speed protection from wrong connection, over current and HI voltage spikes on the lines wires and it solves all problems.

I was looking at the CM201, one of the chips is a HD74HC245 driver, the other two are two TI chips but I can't read which. Anyway, sockets in itself is a source of issue in electronics, and there are many reasons for that. Yes, I know very well that the advantage is that it is easy to change a chip if you blow it, but perhaps it is too easy... ;) Any professional electronic repairman can EASILY swap a blown DIL chip, even if it is soldered. Sockets give the DIY impression, not professional at all.

In a product for $165 I don't want to see sockets, and as Balázs pointed out, relays are also supposed to be on a separate card or separate all together, so you can install them on DIN rail after needs, and swap easily if necessary, once their end of life is reached. As it is, the card has sockets for some chips but not for the relays and it should be the opposite, if the relays are on the same card. I also don't like the way the relays are located, seems like low voltage and high voltage relay contact tracks are mixed and the relay contacts are too far from the screw terminals. Also, the relays are severely underrated, 7A 120VAC is a joke, even my £5 BOB uses 10 250V relays and the relay outputs are immediately at the screw terminals. Those relays can only be used to activate other relays, not actually for switching on/off any high voltage devices. In other words, they only provide the function of galvanic isolation. Sorry, but for that price I'd expect more than that.
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