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Hello,

in most of my intended applications using the V130/ V350, data logging plays a very important part - and consequently data handling!

As much as we like the micro SD cards as storage medium, to transfer data regularily with big hands it is not advisible - especially if an enclosure / box has to be opened in not really clean environment .....

Good would be a USB connector, using a USB stick ....

So I tested a microSD/ SD extension cable which can easily be found..

But the results were not good at all, lots of errors in the file structure (and csv files), assume the cable quality was not good/ too long (23cm) and noise very likely the cause of this. Besides the Card in/out signal is not much good using an extension cable.

I assume this or similar problems have occured before in regards to data logging with SD; has anybody some experience with SD extension cables ? Or any other better idea?

Thanks

Beka

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Go wireless. Put a bluetooth or Wifi adapter on the RS232 port and upoad the data that way. If you go Wifi you could patch it into your main network and then you wouldn't have to leave you seat.

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Thanks for the comments .... and more info about my applications:

- the Com port is already taken, so no BT / serial possible, besides

- my clients are agricultural operators out in the field , no way they will/ should handle these procedures,

- must be as simple as possible like swapping cards from time to time (so have 3G router for remote data transfer as well, but still need "safe" procedure)

Thanks, Beka

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You can mount more than 1 com port on the device. If setup properly, it should be as simple as pushing a button on the display to "send". If you wanted to go with GSM, you could even automate it entirely and take the people completely out of the equation.

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Damian,

still not clear...

- only 1 com port possible if I understand the manual correctly, as we use LAN card as well for the 3G LAN router

- and reception here is pretty bad if we have reception at ALL (that has been the idea to use 3G or alike, to "take people out" to avoid issues

ONLY way, swapping cards at least in our environment (out in the bush - no WiFi/ GSM )

So as written at top, any suggestion to save securely/ conveniently onto a flash medium

Cheers Beka

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Hi,

To improve cellular connection, I will recommend you to use yagi cellular antenna, not cellular signal booster or extender.

Google on it and find nearest/cheapest suplyer.

BR.

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Hello,

yes agree have had them for test, stationary!

On a moving vehicle (e.g. tractor, harvester) not too good (unless the owner is willing to pay for spares) - and driving through an orchard is a different story again.

To get better coverage we also tested 3G modems with dual - sims - slots, so we can switch to the best signal ...if there is one!

No question without external SD card or USB facility we have difficulties ...

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Hello.

Any SD Card extenders are not supported officially by Unitronics. Reassone for this is simple - long wires are working as antenna and make OPLC unstable.

SD Card formatted in fixed file system and Directory Structure.

USB stick is not a solution, as it needs special drivers etc.

As an alternative, you will collect data when vehicle is at parking slot. There you will use BT or WiFi. For example, 300Mbps Portable Wireless AP/Router of Tenda. Or similar one. Communication will be open when vehicle is in WiFi range.

From here you will start to retrive data.

B.R.

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Thanks AlexUT,

I understand this pretty well, in theory great, but in our environment just not realistic at all!

Mainly these machines e.g. harvesters work during night time or around the clock and "parked" in the field no shed/ garage around. Training people to use a laptop with Wifi etc (I have a 3G Lan router incl. Wifi) for retrieving data for example in a car - NO WAY!

My existing unit has a SD card slot, just very simple.

As said our plan is to use both possibilty, if possible data transfer (and other functions, like trouble shooting) via 3G Lan router and SD card as backup and in situation where there is no coverage or bad signal.

A pity, Unitronic's Visilogic is an excellent software - the best I have seen so far!

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Hi Beka,

I agree with you. And - frankly speaking, you're not the first person to ask (and insisting on that) for such extender. But Alex is right - such extender is very dangerous for the card and the congtroller. I have no right to recommend such accessory. I know customers are using it, but on their own responsability!

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For my two cents worth, regarding antenna, I would suggest high-gain Omni directional. Expecially since it is on a mobile platform. With a yagi it needs to be aimed at the tower, which may not be practical on a vehicle.

We have had the discussion about extending the SD card in relation to mining applications as well. Really the SD card ends up being a permanent memory expansion, not a removable storage in these kind of outdoor situations.

I have also toyed with the idea of using RFID tags. The PLC can be programmed to load the data onto the tag when placed near the read/write head, also with some touch screen interaction. Then also have a reader on the PC to retrieve the data. It would require some intensive programming to set up initially, and is limited by the available tag memory, but also has some nice features including robustness. You could interface via Ethernet, or possibly CAN.

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I brought this up a few years ago on the forum for an OEM application. We didn't get the order because there was no easy way to get the data off the card without opening the door. The only way to truly address this is to add USB host capability to our PLC. You can easily extend the USB port.

Joe T.

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Joe, I totally agree.

seems I am in a similar position (finishing our project and getting orders if I can find a way for simple data transfer). Though there are other devices e.g. with USB, I believe Visilogic and Unitronics support are unequalled!

Beka

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Thanks AG automation and Simon,

I can implement WiFi via the 3G LAN router already - again I need a simple methode for simple data transfer. It is very unlikely that an operator or even orchard manager brings his laptop/ smartphone routinely close to the PLC for downloading. Maybe twice but not more during very stressy harvest time; Swaping a SD card or USB stick is just too simple!

These WiFi cards look interesting, though only for SD not micro SDs as found with V130/ 350.

Cheers Beka

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How about transferring the info through the ethernet port to a cheap netbook and then to a USB stick?

Maybe this is not any better than my previous thought. I am not certain if you could have it automatically transfer directly to the USB stick on the netbook with Unitronics software or not. But there should be some way. But I guess that is still a little combersome. thought maybe would be another option. then use the netbook to display a video camera to help make an exuse of why it is needed.

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