low cost 36 channel 24 volt datalogger

[Andy32821]

Hi Everyone,

I am looking for a low cost 36 channel stand alone datalogger that will monitor 24 volt solenoids for one week. One minute sample rate per channel is all I need. I do not even need the voltage quantified. Just on or off.

Power is available at the test sites so it does not need to be battery operated. USB to retrieve the data would be ideal.

I don’t want to build voltage dividers and would like the unit to read 24 volt ac directly.
The smaller the unit the better, but cost is the main factor.

Thanks,
Andy

 

[ScottyUK]

Loggers with AC inputs tend to be high bandwidth in order to digitise the AC waveform and are expensive, especially multichannel units. If you use your 24V AC to drive a relay coil you will have a digital signal available from the relay contacts which will be much easier to interface to a cheap logger. Something like

http://www.omega.co.uk/ppt/pptsc.asp?ref=CIO-DIO48

perhaps.

When you say cost is important, what do you consider 'cheap' and what do you consider 'expensive'? £1000 = expensive? £10,000 = cheap? Without some figures to work against, "cost is the main factor" is a pretty meaningless observation. We don't know if you are a one-man-band or a government research facility.

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I don't suffer from insanity. I enjoy it...

 

[Andy32821]

Hi Scotty,

I need to validate the actual outputs (on or off)leaving the cabinet every minute over a weeks time. I'm looking for a standalone black box (not connected to a computer until ready for download)I can lock inside a control cabinet and retrieve a week later. (Hopefull data I can dump to excel.)

That less than 1/2 meg of bits storage needed. Only 12 meg if 32 bit bytes are taken each minute.

I am looking in the under $1000 range.

Thanks,
Andy

 

[ScottyUK]

Grant Instruments make some nice data acquisition gear. It's a long time since I bought one of their products and the range is kinda different to the one I remember - a lot of new devices. Their tech sales guys were pretty clued up last time I spoke to them.

http://www.grant-dataacquisition.com/

The following link looks like a possibility, if you can arrange a digital signal from the solenoid or from the solenoid driver. Cost looks to be in your ballpark - $725. You can spend the other $275 on arranging some digital signals from your solenoids! I've no experience with this company's products: I found it on Google by searching on "low cost data acquisition" without the " ". A lot of hits are for PC-based hardware, but there are some stand alone ones in there too.

http://www.datx.com/products_hardware/prod_dt9835.htm

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I don't suffer from insanity. I enjoy it...

 

[itsmoked]

I can vouch for that company. It is packed with EE's and is a major player in Data Acquisition in the USA. Generally their stuff is pretty pricey. That item looks pretty good Scotty.

Keith Cress
Flamin Systems, Inc.-

http://www.flaminsystems.com

 

[ScottyUK]

Thanks Keith. I'm always wary of recommending products I haven't actually used.

Andy,
Couple of major questions: do you have mains power at the location? If not, how much energy storage or generation do you have?

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I don't suffer from insanity. I enjoy it...