Initial setup and test of EKM v.4 meter

General questions and discussions focused around the EKM Metering System. Discuss your meters, installations, and meter communications here.
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MohaveTom
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Joined: Wed Aug 12, 2015 2:29 pm

Initial setup and test of EKM v.4 meter

Post by MohaveTom »

I just received my EKM v.4 meter, 2 CTs, 1 USB to RS485 Converter, and 2 Zigbee communicators. The meter and one Zigbee will be located about 120' from the other Zigbee and the USB converter.

I see from the installation document that the outputs from the meter may be used to power a Zigbee. Since these outputs are programmable, I need to make sure they are programmed to power the Zigbee, but if I install the meter in its eventual location, I will not be able to have computer access to it directly. If the default configuration of the outputs does not power the Zigbee, I will have no access. Therefore, I would like to power up the meter on my test bench and configure it before installing it. Can I just put 110V power to the meter (On L1 and N) for testing purposes? With no CTs connected. If so, I can test and configure the meter and test the Zigbees under lab conditions before trying to put them in the field.

The 5v+ connection on the USB converter is for biasing the RS485 signals, NOT for powering the Zigbee. Forum posts indicate that for shortish cables (tens of feet) from the Zigbee to the meter or USB converter should not need biasing or terminating resistors. Is that correct?

Thanks
Tom
Jameson
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Re: Initial setup and test of EKM v.4 meter

Post by Jameson »

Hi Tom, Welcome to the forums!

You sound like you really have it dialed before even getting started! :lol:

1. Yes, absolutely set it up on your test bench using just 120 volts AC to power it up. You do not need a CT connected for this step. This will be sufficient so that you can establish meter communications with the USB and make meter settings.

(As a matter of fact, I recommend this. Get everything working in a minimal fashion, understand how the meter and software works on the bench, make sure everything seems right, and then go install it. Too many installers drive 200+ miles, install everything, and then figure out there is something they missed. Save a lot of time by spending a little time up front.)

2. Connect your meter to the USB converter over RS485 with A to A and B to B.

3. Once it is on your bench you will want to set one of the relay outputs to "ON". You can do this using your USB converter and the EKM Dash software. This step is covered in Fig. 15 here: http://documents.ekmmetering.com/EKM-Da ... Manual.pdf

If you unpower the meter at this point and then go install it, this relay will come back "ON". It will provide 50mA of 12 VDC, which is enough to power the 485Bee. Having the Omnimeter Pulse v.4 power the 485Bee saves you the hassle of installing a 120 volt socket near the meter and using a wall wart to get 12 volt power.

4. I would ignore the 5v+ and the Ground on the USB converter. I would only use the RS485 A+ and B- ports. You will not need to use biasing or terminating resistors for either install. It is very rare to need these in our installs.

Good luck
Jameson
EKM METERING
http://www.ekmmetering.com
831.425.7371
MohaveTom
Posts: 8
Joined: Wed Aug 12, 2015 2:29 pm

Re: Initial setup and test of EKM v.4 meter

Post by MohaveTom »

Thanks Jameson for the quick response.

I have powered up the meter, and connected the USB converter, B- to B- and A+ to A+.
I configured the meter in EKM Dash, using the USB connection on my Mac "usbserial-AH034Y93".
The USB converter flashes when plugged in.
The USB converter flashes blue every 10 sec or so, and occasionally flashes red.
I seem to be getting about 40% successful meter reads; that is, 60% of the time I get
"300002570 No Response - Check RS485 Connections and Meter Number" and 40% I get
"300002570 1 Successful Meter Read".

I have ohmed the connections from the meter to the USB converter -- all good. I have replaced the shielded twisted wire with speaker wire with no change in behavior.
Here's EKMDash activity.
EKMDash activity20150813.jpg
EKMDash activity20150813.jpg (112.16 KiB) Viewed 16138 times
Here's a picture of the wiring. (Black wire jackets are nearly aligned.)
MeterToUSBWiring.jpg
MeterToUSBWiring.jpg (100.13 KiB) Viewed 16138 times
Jameson
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Joined: Fri Nov 04, 2011 7:42 pm
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Re: Initial setup and test of EKM v.4 meter

Post by Jameson »

Yes, you should be able to get 100% good reads with this setup.

The first thing that jumps out at me is the wire you are using. It looks like a black shielded cable with 2 red wires and 2 black wires. It looks like the wires go from the meter through the black jacket then back through the jacket and to the USB converter.

What if you just replace this with a 24AWG twisted pair from a CAT5 cable? You should get 100% good meter reads.
Jameson
EKM METERING
http://www.ekmmetering.com
831.425.7371
MohaveTom
Posts: 8
Joined: Wed Aug 12, 2015 2:29 pm

Re: Initial setup and test of EKM v.4 meter

Post by MohaveTom »

I tried ~2 feet of speaker wire with the same results. The setup I took a picture of was using shielded twisted pair (one red, one black). In the picture the two ends of the ~15 foot cable were nearly aligned so they looked like one big cable.

I'll cut up an extra 1 meter Cat5 patch cord and try that. I don't expect any difference because cross-talk issues are minimal for the short lengths I'm using.
MohaveTom
Posts: 8
Joined: Wed Aug 12, 2015 2:29 pm

Re: Initial setup and test of EKM v.4 meter

Post by MohaveTom »

Indeed, using Cat5 patch cable works the same. I have Green connected to B- on both the meter and the USB; and I have White/Green connected to A+ on both.
MohaveTom
Posts: 8
Joined: Wed Aug 12, 2015 2:29 pm

Re: Initial setup and test of EKM v.4 meter

Post by MohaveTom »

I don't think it is relevant, but my computer is a Mac Pro (Mid 2010); the USB port is USB2. I will send a "system report" if desired.

Oh, also OS X 10.10.4.
Jameson
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Re: Initial setup and test of EKM v.4 meter

Post by Jameson »

We are mostly on Mac here, so you should be fine.

You have connected and disconnected your different wires enough times with the same results that I cant imagine it has something to do with the terminal block connection.

So that narrows it down to a USB issue, or a meter issue, or an issue with the Dash.

First try restarting the EKM Dash software, if this dosn't help restart your computer. I have seen an issue on a Mac before where every other read was good (not exactly what you are seeing), and I seem to recall it was fixed with a restart.

Let me know how it works out. Thanks!
Jameson
EKM METERING
http://www.ekmmetering.com
831.425.7371
MohaveTom
Posts: 8
Joined: Wed Aug 12, 2015 2:29 pm

Re: Initial setup and test of EKM v.4 meter

Post by MohaveTom »

Restarting EKM Dash didn't make any difference. Restarting the computer WORKED!!

Perhaps it is important to restart after installing the USB driver?

Thanks
Tom
Jameson
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Re: Initial setup and test of EKM v.4 meter

Post by Jameson »

Great to hear! That really is an edge case bug in the worst place! Call it the first impression bug.

I would surmise that it only happens in newly minted Macs of a certain OSX version using the FTDI driver for the USB converter. It sounds similar to the every other read is a good read bug, that now that I think of it was on a newly minted Mac also.

We will look into it.

After all, you only get one chance at a first impression :P Thanks for letting us know.
Jameson
EKM METERING
http://www.ekmmetering.com
831.425.7371
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