Datalogging

[mgookin]

I need to get some dataloggers set up. We will be logging voltage only. For discussion purposes let's just say I need to get one system set up. Here are the requirements:

Store minimum 30 days of data.
Log voltage only.

When I look at Fluke all I come across are the Fluke 287 & 289 and they only hold 10,000 and 15,000 records respectively.

There is the Extech/ FLIR DL160 which has 256,000 records. At one per second that only gives me 256k/84,600= 3 days. If I bump it to one per 12 seconds (5 per minute) I can stretch that to 35 days, but what good is 5 second interval data?

On a Fluke page of a discontinued product (Fluke 189) it said up to 400 hours with extended battery pack. That 400 hours is 16 days. I don't care about battery life; I can build whatever power supply I need. It's the data records I need.

I know there are people on here who have continuous datalogging. How do you do it?

My only restriction is I don't want to have to have a pc out in the field environment due to weather, theft and relying on it to stay on. There is plenty of power available to have big batteries, chargers - everything needed and I can secure or hide that stuff.

As far as number of records/ time the system can run, is that Extech instrument the best there is? Or am I misunderstanding something?

 

[iwire]

, but what good is 5 second interval data?

Very good, or very poor depending on what you are looking for.

What event are you trying to capture?

 

[StarCat]

Amec

Amec

There is an outfit called AMEC that makes a large variety of these devices. I do not have personal experience with their product.

 

[Cow]

First things first, what sample rate do you need for 30 days?

 

[gar]

140602-1944 EDT

mgookin:

I regularly monitor my line voltage, and power and energy consumption, with a TED 1000 System. This has 1 second resolution. The 5000 system implies 1 second, but the finest is about 2 seconds changing to about 5 seconds at times.

As supplied by TED the 1000 system requires a computer for collection, and can not hold more than somewhat more than 24 hours, before the data must be saved.

If I just use the 1000 MTU and build my own collection device, then I can save as much data as an associated hard disk can store.

If you want to monitor thru a loss of AC power to the MTU, then the MTU must be modified to be powered from an external source that is not the voltage being measured. From looking at the circuit I believe this is fairly easy.

For finer time resolution the program in the MTU could be rewritten. One second resolution is fairly useful, but finer, like 100 mS, could be more useful in some applications.

The original 1000 MTUs are no longer available, however, the replacement unit is probably equally useful for most application. The replacement unit has less power resolution.

.

 

[gadfly56]

See if this works for you.

 

[PetrosA]

If you don't need current logged, this PEL 102 (no sensors) might be just the ticket for you. It accepts up to 32 GB SDHC cards:

http://www.transcat.com/catalog/productdetail.aspx?itemnum=2137.61-PROMO

 

[mgookin]

Thanks everyone for the excellent suggestions.

Realizing that RMS logging is a flat line and not a sine wave, I don't need so many data points. And each point gives min & max if I use that Extech/ Flir meter. It also has 2 channels allowing me to log both line & load. And I won't need a pc out in the field. At $300 each that's an acceptable risk. I'll power it off the a/c adapter and put it on a small UPS.

Thanks again! :thumbsup:

 

[GeorgeB]

mgookin, I do data acquisition on a regular basis monitoring hydraulic pressures, flows, levels, positions, command signals, and feedback signals.

Dataq, www;dataq.com, makes the hardware (and free software) I use, and I recommend it. There are versions which accept SD cards (note, not SDHC, and the cards must be high spec) for standalone use; I've never done that, preferring a PC at the application or via an Ethernet connection.

For under $1000, you can get their DI-718B-US with an isolation amplifier for RMS line voltage ... 0-150V so a PT of some sort would be required, and a SD card.

Additional channels add about $170 in RMS and you can go to 8 ... signals can be mixed ...

 

[mgookin]

mgookin, I do data acquisition on a regular basis monitoring hydraulic pressures, flows, levels, positions, command signals, and feedback signals.

Dataq, www;dataq.com, makes the hardware (and free software) I use, and I recommend it. There are versions which accept SD cards (note, not SDHC, and the cards must be high spec) for standalone use; I've never done that, preferring a PC at the application or via an Ethernet connection.

For under $1000, you can get their DI-718B-US with an isolation amplifier for RMS line voltage ... 0-150V so a PT of some sort would be required, and a SD card.

Additional channels add about $170 in RMS and you can go to 8 ... signals can be mixed ...

Thanks George, but we have remote test stations out in the Everglades (a swamp) and would rather give it a shot with the $300 instrument first.

We have to expect that one day we'll lose at least one test station even though we haven't lost any yet.