IO Link Vs Murr Cube 67

Can anyone elaborate on the differences on how these technologies work?

It sounds similar, but IO Link adds the addition of sending parameters to the sensor. As far as deploying this system in the field and having fewer cables to run, which system is wins or the pros and cons of each?


Thank you!

Well, as a data point: you can add a I/O block to your Cube 67+ network that includes IO Link ports. We are using it and it works fine.

We recently compared a handful of remote I/O systems, including IO-Link and Murr's Cube67, to try and standardize on a method for doing our field wiring for machinery. In the end IO-Link was the winner for us. Some people were surprised to hear that we considered IO-Link for remote I/O (mainly salespeople hocking other systems). It seems to be more known for "smart sensors" and such, but we found it to be a very capable contender for I/O expandability.

To me, one of the biggest advantages of IO-Link is that it uses standard non-shielded M12 sensor cables for the drops to the I/O boxes. We started stocking all the different common lengths of double-ended cables, so when you're working on field wiring you just grab the lengths you need. One disadvantage is that you can't daisy chain devices, i.e. all slave nodes have to be in a star topology from the master. (There is one exception to this... some of Balluff's nodes allow you to daisy chain one additional device.) With proper planning of the IO-Link master hubs and your top level fieldbus, I don't see this as too much of a restriction.

My biggest beef with the Cube67 system is that it's completely proprietary. It's very flexible as far as topology and layout, but you're completely locked in to Murr for replacement parts and expansion. The connection between nodes uses 6-pin M12 cables which, although not unique to Murr, are certainly less common than 4-pin and more expensive. One of our considerations was, if we need to expand the remote I/O network in 1/5/10/20 years, what platform is more likely to still be available? I expect Murr will still be in business but will they still be making a compatible product line? With IO-Link you aren't locked in to a specific brand. So far we have mixed and matched Balluff/IFM/Banner/Beckhoff without issue. (Oddly, the one IO-Link device we did have trouble with was from Murr.) I've heard people say IO-Link is a fad but that isn't my impression.

Let me be clear, IO-Link isn't a replacement for a top level fieldbus. We are using EtherCAT which is super fast but we didn't want to run Ethernet and power cables everywhere. In cases where IO-Link doesn't cut it (say, for a high speed sensor) we can always fall back on EtherCAT and just deal with the extra cabling. But for us this is the exception, not the rule.

kolyur said:

We recently compared a handful of remote I/O systems, including IO-Link and Murr's Cube67, to try and standardize on a method for doing our field wiring for machinery. In the end IO-Link was the winner for us. Some people were surprised to hear that we considered IO-Link for remote I/O (mainly salespeople hocking other systems). It seems to be more known for "smart sensors" and such, but we found it to be a very capable contender for I/O expandability.

To me, one of the biggest advantages of IO-Link is that it uses standard non-shielded M12 sensor cables for the drops to the I/O boxes. We started stocking all the different common lengths of double-ended cables, so when you're working on field wiring you just grab the lengths you need. One disadvantage is that you can't daisy chain devices, i.e. all slave nodes have to be in a star topology from the master. (There is one exception to this... some of Balluff's nodes allow you to daisy chain one additional device.) With proper planning of the IO-Link master hubs and your top level fieldbus, I don't see this as too much of a restriction.

My biggest beef with the Cube67 system is that it's completely proprietary. It's very flexible as far as topology and layout, but you're completely locked in to Murr for replacement parts and expansion. The connection between nodes uses 6-pin M12 cables which, although not unique to Murr, are certainly less common than 4-pin and more expensive. One of our considerations was, if we need to expand the remote I/O network in 1/5/10/20 years, what platform is more likely to still be available? I expect Murr will still be in business but will they still be making a compatible product line? With IO-Link you aren't locked in to a specific brand. So far we have mixed and matched Balluff/IFM/Banner/Beckhoff without issue. (Oddly, the one IO-Link device we did have trouble with was from Murr.) I've heard people say IO-Link is a fad but that isn't my impression.

Let me be clear, IO-Link isn't a replacement for a top level fieldbus. We are using EtherCAT which is super fast but we didn't want to run Ethernet and power cables everywhere. In cases where IO-Link doesn't cut it (say, for a high speed sensor) we can always fall back on EtherCAT and just deal with the extra cabling. But for us this is the exception, not the rule.

Click to expand...

Wow, thank you for all of this information. I was thinking that may be one of the draw backs, was the lack of being able to daisy chain.

So for every master, how much field IO ports can I put out there? I don't have to use IO Link sensors on IO Link ports and visa versa? Also, I found IO Link safety. Have you ever used that? How many inputs could you squeeze out of one master (Digital)?

I've never seen a full IO Link system, so I'm excited to hear about its ability. What about cost? have you found it to be comparable or different in price for a system? What about the difference in cost from one IO block to an entire plant? I noticed with the cubes the cost is high for a small scale network of them.

Timeismoney08 said:

Wow, thank you for all of this information. I was thinking that may be one of the draw backs, was the lack of being able to daisy chain.

So for every master, how much field IO ports can I put out there? I don't have to use IO Link sensors on IO Link ports and visa versa? Also, I found IO Link safety. Have you ever used that? How many inputs could you squeeze out of one master (Digital)?

I've never seen a full IO Link system, so I'm excited to hear about its ability. What about cost? have you found it to be comparable or different in price for a system? What about the difference in cost from one IO block to an entire plant? I noticed with the cubes the cost is high for a small scale network of them.

Click to expand...

I've seen IO link masters that support anywhere from 4 to 16 IO link ports. I think one IO link port can handle up to 16 digital inputs, or one analog/smart sensor.

I've never used the Murr cube stuff, but I'd expect it to be in the same range. It definitely costs more than the equivalent IP20 IO rack, but less than individual networked IP65 IO blocks. IO Link is slower than Ethernet, but serial over 3 wires is way cheaper than an ethernet port.

I've seen safety over IO Link a couple times, but I think that so far it was one proprietary implementation. It worked, though. I think the IO Link group is working on a safety protocol, but it definitely isn't around yet.

mk42 said:

I've seen IO link masters that support anywhere from 4 to 16 IO link ports. I think one IO link port can handle up to 16 digital inputs, or one analog/smart sensor.

I've never used the Murr cube stuff, but I'd expect it to be in the same range. It definitely costs more than the equivalent IP20 IO rack, but less than individual networked IP65 IO blocks. IO Link is slower than Ethernet, but serial over 3 wires is way cheaper than an ethernet port.

I've seen safety over IO Link a couple times, but I think that so far it was one proprietary implementation. It worked, though. I think the IO Link group is working on a safety protocol, but it definitely isn't around yet.

Click to expand...

Any other Field IO companies have standardized on? I like the two systems so far.

Timeismoney08 said:

Wow, thank you for all of this information. I was thinking that may be one of the draw backs, was the lack of being able to daisy chain.

So for every master, how much field IO ports can I put out there? I don't have to use IO Link sensors on IO Link ports and visa versa? Also, I found IO Link safety. Have you ever used that? How many inputs could you squeeze out of one master (Digital)?

I've never seen a full IO Link system, so I'm excited to hear about its ability. What about cost? have you found it to be comparable or different in price for a system? What about the difference in cost from one IO block to an entire plant? I noticed with the cubes the cost is high for a small scale network of them.

Click to expand...

I'll give you some details about Balluff's IO-Link offerings that may answer your questions. I am in no way promoting Balluff over other brands, it's just what we've used so I'm most familiar with it. I know that IFM is another big player in the IO-Link market (and generally cheaper I'm told).

With Balluff you can get 4- or 8-port master blocks. There is a 16-port I think but it is not available with all fieldbus options. Each port on the master can be configured as a standard digital input, digital output, or IO-Link port. If used for IO-Link, you can connect a single IO-Link device. Balluff offers slave IO blocks with up to 16 digital inputs or outputs in M8 or M12 ports. So the most I/O you could get per master would be 16x8=128 digital points. Balluff does offer modules that allow you to daisy chain a second module from the last port on the first one. So if you maxed out this capability your total digital I/O count per master would be (14+16)x8=240 points. In our applications we tend to put multiple masters at various strategic points around the machine, being sure to leave some unused ports for future expansion. The only limit to how many masters you can have is the overhead it adds to your fieldbus.

Cost wise, we found IO-Link to be pretty competitive with other options. The master blocks from Balluff are a bit pricey but they're built like a tank. The 8-port master is about 50% higher than the Cube67 bus node we had quoted, but everything else in an IO-Link system--slave I/O blocks and cables--tends to be cheaper. It's hard to do a generic comparison because with IO-Link you might need multiple master blocks depending on your I/O count, but with Cube67 there's generally just one bus node. I've heard that IFM's IO-Link masters are cheaper but they use a funky keyed M12 cable for the power connection and I didn't want to have to stock yet another type of cable. IO-Link I/O blocks from most manufacturers can be as low as $150 and go up with ruggedness and features. Balluff also has IO-Link valve interface cables that plugs into the DB25 connectors on many manufacturers' valve banks.

One feature I like about Balluff's master blocks (Cube67 has this also I believe) is that the power connector has separate connections for sensor power and actuator power. Sensor power would be on constant while actuator power can go through your safety system. So during an E-stop, for example, the power for your digital inputs can remain on while all outputs and valves shut off. I've seen references to safety over IO-Link but haven't used it and it seems to be in its infancy.

IO-Link devices use a device description file (IODD), similar to other fieldbuses. This is an XML file that basically defines how much data is transferred between the device and master, and what the individual bits/bytes represent. It's mainly a convenience for the programmer, but if you don't use it you have to figure out the addressing yourself using the manual. With Balluff's master blocks, to use IODDs you have to upload them to the master using the web interface which I've found to be a PITA. I'm not sure how other brands of master blocks handle this.