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Generac Generator "Wireless Status" protocol?

Posted by cnr1089 (My Page) on
Fri, Oct 19, 12 at 22:27

I have a Generac Guardian 20 kW generator.

I noticed there is a 100-300$ wireless monitor system. I am pretty handy with micro controllers and doing this myself. I am curious, if anyone knows how the wireless receiver (the part on the generator) communicates with the main controller?

From the install instructions found here

It looks as if there is Power/Ground and 1 Data wire. So, possibly just Serial (UART)?


Follow-Up Postings:

RE: Generac Generator "Wireless Status" protocol?

Don't know about the 20K but on my 80k, it's an RS-422 serial interface for the remote control unit.

RE: Generac Generator "Wireless Status" protocol?

Did you have any luck with this? I came across the same install manual and presumed power, ground, data. But the wireless remote has 2-way communication, so it might be something more complicated than a regular serial port.

The install notes for the MobileLink (one-way cellular based monitoring) are found here:

They mention a 6-pin harness on the mobilelink side (only appears that 3 or 4 wires are populated). It seems to use the same 8-pin accessory connector, and they also mention that for this unit the power lines get hooked directly to the battery - maybe it uses more power than the accessory port can handle.

The simpler 3-light wireless module seems to tap into the wiring harness for the status LED's on the top of the generator, rather than use the serial port:

RE: Generac Generator "Wireless Status" protocol?

I'm very interested in this too. Just got the 14kw Generac model and it came with a free 12 month mobilelink subscription but curious how I can leverage an arduino or other microcontroller to monitor the 8 pin accessory output without the subscription fees that come with mobilelink.

RE: Generac Generator "Wireless Status" protocol?

First off, you only need the subscription if you are using the MOBILELINK (cellular device). If you just want local control you can plug other devices into that port instead. Generac makes a wireless LOCAL link (so you can watch it from inside the house somewhere) that doesn't require a subscription.

The interface is RS-422 I'm fairly sure. You can get adapters to connect it to various devices. I've not bothered trying to hack mine yet.

RE: Generac Generator "Wireless Status" protocol?

In response to tonnatalie, yes, I agree the subscription is required only if I want to use the mobilelink service but what I envisioned was connecting a microcontroller (such as an arduino) and have it monitor for the same errors/alerts/messages that the mobile link device transmits.

The benefit here is that one could then use other protocols such as wi-fi to transmit the data to a computer inside or, better yet, a server offsite where it can be logged, accessed remotely or sent via text message when updates received.

I realize that's basically what the mobilelink does (except they use cell transmissions for the data) which has it's pros & cons in my opinion:

+ Good because it's easier to set up and is not dependent on wifi being live like my home-brew solution (the wi-fi issue could be addressed a couple different ways I'm sure)

- Bad because it costs $5-10/month in extra fees + the equipment for anyone who doesn't have the $250 unit already.

I like the idea of having my own solution in place plus I enjoy trying to figure this stuff out (see my blog for info on a sump pit water level monitor I built using similar microcontroller in the link below)

Back to the generator monitor question at hand...
I've had my Generac 14kw fr a week now and have seen the following status codes come through on the mobilelink during setup and initial runs.

I assume there are more fault codes to consider but would be interested in hearing if anyone figures out how these are sent/can be read from the accessory port.

Codes seen so far:
1. Your generator is ready to run.
2. Your generator is running in exercise mode.
3. The generator has been set to the OFF position and will not start automatically in response to an outage.
4. Your generator is running due to utility power being lost.
5. The generator has been set to the OFF position and will not start automatically in response to an outage.
6. The generator has been set to manual operation and is running.
7. The battery charge level is too low. Please inspect/replace the battery or call your service/maintenance provider.
8. AC power to your generator's battery charger has been lost. Please check the circuit or contact your service/maintenance provider for assistance.
9. Your unit has blown the fuse or the fuse is missing (E2400). Please reference your owner's manual to replace the fuse or contact your service/maintenance provider.

Here is a link that might be useful: my sump-pit water level monitor

RE: Generac Generator "Wireless Status" protocol?

You don't even need an Ardino. You can purchase an RS-422 to RS-232 converter and then something like the GlobalCache serial to wifi interface. I've used that to talk to other devices. You just open a socket to port 4998 (if I recall properly) and send and receive.

RE: Generac Generator "Wireless Status" protocol?

Did you ever get anywhere with this? I had a 10KW with nexus controller installed last fall, I've got a couple of RS485/422 converters from previous projects, but I've not found any pinout information on the connector used for the Generac remotes ..

RE: Generac Generator "Wireless Status" protocol?

Looks like the pseudo-standard DB-9 on mine. The bigger issue is the protocol on the wire. I thought I saw the connections in one of the docs but they're down at the site right now.

RE: Generac Generator "Wireless Status" protocol?

I would be very interested in this project, as I assumed many others would be. The downside to the mobile link has already been listed, it is a pay per month service, cellular versus local wireless and you would have to purchase their expensive hardware. Add to that you do not have control of the logging or data (it is on their website) and you have all the reasons you need to create an arduino or similar solution.

Here is what I have been able to find so far, this is a 3 wire (with ground) serial connection and is very likely using modbus. If it is in fact Modbus, one should be able to slave a laptop to a serial link with the mobilelink on it, and sniff the activity on the wire to see what is data / commands are available. In looking elsewhere on the web, it seems as if OMNIMETRIX also makes a solution for generac, i would guess mobilelink was generac direct answer to it. That solution can monitor several activities that are listed here in the generac link

I seenow indication that omnimetrix is a partner of generac nor that generac opens the controller with an API, etc., so my guess is that what they can see is readily available from the controller's serial port.

This info should get someone started... I do not have enough experience "yet" to build any of these arduino, pi, intel controlellrs myself, but I would be willing to help where i could. If there is enough like minded people on this, maybe we can start a project website.

RE: Generac Generator "Wireless Status" protocol?

I have not had a chance to make any progress on this due to the weather but glad to see more people on this thread. I plan on taking a closer look at the hardware interface once the weather improves a bit here in Chicago.

I haven't played with wireless interfaces before but reading up on serial communications over XBee or similar hardware to communicate with a remote PC a inside the house (a hundred or so feet away).

Thanks for the link to Omnimetrix...reading up on that now.

RE: Generac Generator "Wireless Status" protocol?

I'm also interested in this. I have a 20k with the wireless monitor unit posted in the first posting. I've been looking into this for a while and stubble upon this thread which has provide some insight. I know that the wireless monitoring unit is a freescale design version of the xbee design.

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