Alan Case said:
Advantages of an industrial switch are:
Higher temperature rating
Higher MTBF (mean time between failures)
24V powered with a terminal connection. (No plug pack required)
Din rail mountable
The above info is for unmanaged switches, its another ball game if we start talking managed switches.
Regards Alan Case
Higher temperature rating won't be an issue.
Higher MTBF makes this a must. (Thanks for info)
We have 230V but will use 24V if it's an option.
Din rail mountable, hmm... the cabinet is 2+ meters high, pretty wide and pretty deep, and the only things in it is the CompactLogix, a little 24V powersupply and the PV in the front. I think I can manage to find place for a switch that isn't din rail mountable
lol. Don't ask me why the cabinet has to be that big, it looks ridiculous ^^. But of course it's easier to fit it on a din rail.
I'll have to look up managed/unmanaged, but it looks to me as if it has something to do with network surveillance.
JesperMP said:
If you are a little bit picky about how "correct" you want your installation to be, then you absolutely cannot use any home/office grade equipment in an industrial installation.
In EU your installation must have a CE declaration of conformity (with your signature !), and to put it very short this means that all equipment must be CE approved to EN 61000-6-2 (immunity aginst noise), and EN 61000-6-4 (limit to amount of radiated noise). The CE tick that you find on all equipment is actually classified in two groups, one group for home/office and the other for industrial installations. You cannot mix the two groups in principle.
Now, it is a completely different story how "correct" one should be. I am sure that many installations live happily with non-industrial equipment here and there. And maybe there is a signed declartion of conformity too, so everybody is happy.
For ethernet switches I wouldnt try to save by going for cheap stuff. There are plenty reasonably cost-effective industrial ethernet switches out there.
For Ethernet/IP, as far as I understand, as a minimum the switches must support QoS and IGMP snooping.
Of course I wan't the installation to be as "correct" as possible, and I understand what you mean. But I thought that installations only had to be CE appoved if the customer specifies that it has to be.
I will get an industrial switch now of course.
I will have to look up QoS and IGMP snooping, cause I don't have a clue what that is.
Jon R said:
Although not a PLC application for which I tend to use Harting, we use managed GE products for our electric fence networks, which although not particularly cheap do come with a lifetime warranty and the support is good.
I am aware of a competitor that has used cheaper devices that aren't even managed and has had several failures resulting in loss of control of the fence which is not what you want in high security applications.
The market is abundant with IP switches but as Jesper has said you need to select the switch to meet your application. If you go managed something else to look at is SNMP, which, if you get software to run it will provide you with reporting on the network switches and system health.
Jon.
SNMP is one more thing I'll have to look up.
This is more complicated than I thought ^^
