BEP CZone Signal Interface, a NMEA 2000 winner

... written for Panbo by Ben Ellison and posted on May 3, 2013

That screen above makes me so happy!  I had been reluctant to give up on Gizmo's standalone tank monitoring system but circumstances forced a change. Had I realized how easy and relatively inexpensive it was to switch the tank senders over to BEP CZone NMEA 2000 monitoring -- and how accurate and flexible the output would be, even to the point of custom (and juvenile) tank labels -- I would have made the leap a long time ago...

Aside from the Volvo Penta engine panels the Wema Tank-level Indicator is the only remaining gauge from when I bought this boat in 2009 and it was probably there when she was launched in 2000. If it works don't fix it, right? But in fact it never worked very well; I just didn't realize it. The Poop Tank in particutlar was highly inconsistent, staying at "0" for unreasonable periods and sometimes jumping to "4/4" seemingly overnight, but didn't it make sense that even a specially protected sliding level sensor might fail after so many years in those conditions?


The situation took a bad turn last September, just before I headed south. Suddenly the fuel tanks showed significantly different readings than they had the day before even though the engine had not even been run. That got my attention and though the readings got consistent again once we started bouncing around a bit yours truly also got more consistent about logging miles, engine hours, and tank in use, and I took further measures, so to speak... 


Yup, I started using a weighted line to occasionally measure fuel tank levels and felt fortunate that the boat's short, straight filler hoses make this easy and fairly accurate (I think). I also think that the tanks are rectangular, which would make a linear measurement equate well to volume, though I avoided assumptions that could get me in trouble. I intended, of course, to replace the Wema gauge or try something else, but didn't actually do anything until using the gauge became a matter of jiggling the on/off knob just so and then it died completely early in the trip north.


Also on the (very long) to-do list was testing some BEP CZone modules, including the Signal Interface which is purportedly capable of reading 240-30 Ohm tank senders like the Wemas. The hardware install could not have been easier. I just snipped the blade connectors off the tank and -12v wires that once went to the Wema gauge  inserted them into the SI's removable terminal strip, added a NMEA 2000 drop to the boat's SimNet network and that was about it. In the photo I tried to show how the module is designed so that you can wire up the gasket and terminal strip away from the module and then put it all together in one easy move. Nice!


Then there was the CZone Configuration Tool, which is a Windows PC program that connects to the modules via a USB CAN Adapter. It seemed daunting at first but I've now managed to configure a few modules with it and I've hardly cracked the manual. I should do some reading though and I already see that there are impressive capabilities I haven't tried yet, but let's focus on the tank configuration screen above. What I love is shown in the bottom window where I am about to set a calibration point using "live data" from the sender. That means I've already been able to set tank percentages based on string measurements made at the same time and when I find a very patient fuel dock I'll be able to set or edit as many points as I want in terms of gallons.
   But equally important, I think, is that this live calibration feature has let me easily observe the sender states. What I've learned so far is that all the Wema senders, even the one submerged in Black Water, are remarkably consistent day-by-day for a tank that hasn't been used and seem to make good sense about what is used. The only exception I've seen so far was a 8-25% wobble in the starboard fuel tank when it was down to 3.5-inches and the boat was rolling mildly, and I seem to have improved that with another level guesstimate. And the story gets even better...


CZone is thought of primarily as distributed power and digital switching system (as discussed after the Miami Show) and that stuff is done using proprietary NMEA 2000 PGNs. That means you can only make the switching work using a CZone display or a Simrad MFD (because Simrad and BEP have a partnership). I can confirm that as I also have a CZone Output module in operation (slickly), but the monitoring modules output standard PGNs as seen on the Raymarine i70 above, as well as on a Garmin GMI 10, a Maretron DSM, a Furuno TZT (fuel only) and elsewhere.
   What doesn't carry across the system are the custom labels. In other words "Black Water" is a tank level category built into NMEA 2000 but "Poop Tank" is a custom label only supported so far by Simrad (though I believe that custom label concept is in N2K, just not widely utilized). At any rate, I'm delighted with what I've found so far, and there's much more yet to report. For instance, those temperatures seen on the NSS8 GoFree screen below are coming from a Maretron TMP 100, and that "Engrm" one, actually block temp, could proof itself invaluable. But consider this: when I do a major fuel fill in New Bedford tomorrow I should be able to see what's happening on an iPad. And whereas I also use fuel and waste tank levels to keep Gizmo trim -- they're all outboard -- I'll be able to use the same screen when pumping overboard (where possible). I don't think I'm going to replace the broken Wema gauge.



Though we haven't finished getting the tank sensors finished up, we've just completed some power distribution work with C-Zone as part of an electronics system overhaul on a Cherubini 48 Schooner. Based around a pair of NSS MFDs the owner can control Tricolor, Running lights, Windex, Steamer, and Foredeck lamps from either MFD (nav station or helm). I'm sorry I failed to take screen shots as the lighting functions also neatly show current draw on each. The C-Zone setup made cockpit control of the above deck lighting a far simpler installation versus setting up a conventional switch panel at the helm.
When we get the tanks done I'll try to send pics. I really think C-Zone will find it's way into more and more refits.

Posted by: Jonathan at May 3, 2013 5:57 PM | Reply

Thanks, Jonathan. Am I guessing correctly that you are a professional marine electronics installer? One issue with the CZone gear is that it is mainly marketed to pros, though several Panbo commenters have been able to buy equipment and get technical support for DIY projects.

For instance, I can only find one retail online source here in the States and I'm a little dubious about the prices stated, like $131 for the Signal Interface module just seems impossibly low. Even the purported Minimum Advertised Price of $237 seems an amazing deal for a module that can handle a mix of six tanks, switches or on/off sensors like high bilge alarms. Plus they don't list the USB CAN Adaptor which is the only other bit needed besides the free Configuration Tool to do what I did with my tanks. Anyone know if Boatersland CZonepricing is for real or other sources:

Incidentally, I've enabled similar nav light switching using the Maretron DCR100, as I wrote about here:

It's been working quite well, including an alarm I've set up to warn of bulb failure (Maretron alarming is trail blazing and will get an entry).

It may sound crazy to have both Maretron and CZone on the same boat, and it's mainly because this boat is a test lab, but actually there's a lot of sensing and monitoring that's not currently duplicated. Goes to show how much is possible as NMEA 2000 bridges power and other systems to instrument and multi-function displays.

Posted by: Ben at May 3, 2013 9:09 PM | Reply

Been watching your progress up the coast. Good stops. Be sure to stop in at Margarets in New Bedford for scallops.
I think what your showing will work on the SallyW to monitor her new fuel tanks, replacing that funny little fourway switch to select sensors. I have the Garmin GMI 10 already. Willing to take some photos of that install for you. Maybe see you in Camden next week.

Posted by: Allan Seymour at May 4, 2013 8:29 AM | Reply

Allan, I ate at Margerates last night! And they had the same EIGHT scallop specials as sister restaurant Elizabeth's did on Wed., which was not a problem ;-)

New Bedford/Fairhaven make a fantastic cruising stop, I think. Besides prowling the yards and fishermen docks, I've been to the museum and also visited Imtra and Edson (both impressive operations). Soon I hope to fill up on what may be the least expensive and freshest diesel in New England, then on to Onset and beyond.

I should be able to show you the CZone tank set up late next week, but only if the Gulf of Maine gets friendly.

Posted by: Ben in reply to Allan Seymour at May 4, 2013 9:38 AM | Reply

Ahh, the Wema tank monitor.Finicky to set up and you never really knew what was going on!
Did any ever work out there in the real world?

Posted by: peter c at May 4, 2013 11:45 AM | Reply

Great story. How are you getting the battery info shown in the final picture.

Posted by: Steve Mason at May 4, 2013 6:42 PM | Reply

Thanks, Steve. The house and engine battery info is coming from a CZone Meter module. It was again a very simple install as I already had a 50 milliamp shunt installed from the Link 1000 system I took off the boat last spring.

Calibration, however, is not so easy. It's not BEP's fault, the tools are there, but in my case I can't set a live point without having the inverter and computer on and I don't know what they draw. Plus, though I know the shunt was quite accurate with the Link, I've complicated things since with the solar panels. Wish I could drop a weighted string into my twin 8D's to measure its amp hour state!

At any rate, I've got it roughly calibrated and it is showing me trends at least. Plus I have some other battery monitors to mess with including an electronic Victron shunt and BMV 600 gauge that can be adapted to NMEA 2000.

Posted by: Ben in reply to Steve Mason at May 4, 2013 7:14 PM | Reply

Hi Ben,

I think the Boatersland prices are legit.

Their below MAP prices once you put them in the cart are pretty similar to what I paid for my modules. Most are slightly more expensive than what I paid (5% - 20%), but the Signal Interface is $20 less than I paid (but it's the cheapest module).

I think the SI is so cheap because it really is the simplest functionality of all the modules.

I think it's only a matter of time before more marine retailers have the gear. It seems that there is a steadily growing group of people using it in rewiring their boats, and finding out what is capable with it.

I was talking last week to a marine electrical business owner here who sells C-zone and has started installing C-Zone systems in rewiring projects. His comment was that the hardest thing was unlearning the way of thinking about traditional wiring looms and functionality so that you can take advantage of the many new features available. I totally agree with that.


Posted by: Taniwha at May 4, 2013 11:02 PM | Reply

Thanks, Paul! I realized that Gemeco offers all the CZone gear wholesale and that I had a copy of their (amazing) 500 page 2013 catalog. The Signal Interface module at $130 via Boatersland is a hair below wholesale so it is a bit of an anomaly, but then again the wholesale cost of a Maretron or Garmin analog-to-N2K adapter for just a single tank is significantly more. Not all the CZone stuff is so reasonable, as you note, but it's not bad.

I hadn't really looked at the Gemeco catalog before, but I sure will use it in the future. I think they list just about every NMEA 2000 sensor, cable, adapter, etc. made by any manufacturer major or minor, and are also strong in several other categories. Plus they include a lot of good reference info. Gemeco is a good reason for DYI folks to cultivate a good relationship with a professional installer or dealer, but the catalog is available online, though without pricing:

Posted by: Ben in reply to Taniwha at May 5, 2013 12:00 PM | Reply


Where can one obtain the "CZone Configuration Tool, which is a Windows PC program"?


Posted by: greyghost at May 6, 2013 7:20 PM | Reply


When I purchased my C-zone components from the Singapore reseller/agent he registered me with BEP and I now get all the software updates emailed to me.

I tried to look at how I got the first software (I can't actually remember since it was 2010) - I assume it was on a disk when I bought the first component, but I couldn't find that. It may have been a link to a download that they sent me.

Anyway, they're good at sending me the updates.

I'm not sure how they'll do it via volume retailers like Boatersland. I assume it'll just come on a cd with the components and you'll register.

You can always try emailing and ask. (That's the email address they give in the Czone manual for the US)

One other thing - you also need their (BEP's) USB interface to use the config tool. I have both Actisense's NGW-1 & Airmar's (that came with the PB200 & I believe is also Actisense's in an OEM package) N2K:USB and couldn't use either (a bit irritating). So don't forget to buy that if you need to configure a Czone system yourself.


Posted by: Taniwha at May 6, 2013 10:06 PM | Reply


Without the USB Can Adapter (pricey bit of kit) or programming, would your experience indicate that the CZone Meter Interface would provide PGNs to my NMEA 2000 network so I could at least monitor battery voltages on my displays?


Posted by: greyghost at May 8, 2013 1:09 PM | Reply

Hi Doug,

I've never done anything without using the software programming and N2K:USB link because my system has about 20 C-zone modules and it was just easier to use the software.

However, I think it should be possible to do what you say.

Each Czone module has the full system configuration in it, so there's no "central processor". This means that if you can configure just one module, then if you have other modules in your network, they'll be automatically configured when you plug in the configured module. So, you need to figure out how to get 1 module configured.

The "Czone Installation Manual" has the following info:

- There are 3 possible ways to configure your network: 1) using the s/w & the USB:N2K gateway, 2) from a Display Interface, 3) by plugging a module with a configuration on it into a network that has not been configured.

- It also lists 16 proprietary PGNs, and then says that it can also pass approx 200 standard N2K pgns, but doesn't list them.

The proprietary PGNs listed are all network management and specific module configuration PGNs, not informational data PGNs, so that would lead me to surmise that almost all of the informative data is transmitted using standard N2K PGNs, including the Meter Interface data (but I don't know that for sure).

That should mean that if your display can read those standard PGNs, then if you can get your network configured, you should be able to see them. Be aware though that many of the displays can't display a lot of the standard PGNs, they seem to have quite limited PGN recognition, so check. The Maretron displays seem to have the biggest list by quite a wide margin.

So, how to get your module configured (the Meter Interface needs to be calibrated, so you need to be able to do that somehow).

1) The USB interface part number is 80-911-0044-00. I couldn't find that listed on the Boatersland site, but I'm sure they can get one. I paid about the same as a Switch Control Interface, which Boatersland has for $165, so I assume they'd charge close to that. I don't think that's too bad if you're going the Czone direction - it'd make the future a lot easier as you add modules.

2) Put a Czone control display into your network - this is probably a good idea if you're thinking of expanding it in future. There are 3 options: 1) The BEP Display Interface ($720 from Boatersland). The negative of the DI for configuration is that it's very tedious going through all the button presses - much easier through the PC s/w; 2) one of the cool touch screens that BEP offers (very expensive - i.e. $000's - we're using one at the nav station - it replaces the traditional Blue Sea breaker switch panel - but we've repalced our entire boat wiring with Czone so figured it was worth investing in), or 3) if you have a Simrad or B&G MFD you can control Czone ( I assume that this includes the configuration options but I don't know that for certain).

3) Find someone with a USB module and the software, and configure your module through them, then plug it into your network. Other non-configured modules will be automatically configured. (but the negative is that I don't think you can then reconfigure your network the same way if you want to change it). I would hope that a Czone installer near you would do that for a reasonable fee if you know the config parameters.

A bit long-winded, but hopefully is detailed enough so that the options are understandable.

It sounds like Ben is doing it one module at a time also, so Ben, how did you configure your module?

I hope this is helpful.


Posted by: Taniwha at May 8, 2013 11:47 PM | Reply

Thanks, Paul. I think you gave good guidance, but I can add more about how the Simrad MFDs and CZone work together.

First note that I too am using the USB CAN Adapter and Configuration software to set up and calibrate the test CZone modules. I'm afraid the Adapter is more expensive here than where you are, but it certainly works well and I suspect that any boater who wants to install CZone themselves should use this set up. I've used it quite often as I've fine tuned my tank and battery calibrations, for instance.

That might not be true if the Simrad displays could configure CZone, but they can not. However, the integration is nonetheless slick. When I first configured Gizmo's CZone system and then turned on the Simrad NSS and NSE they read the configuration and automatically set up nice switching and monitoring pages that come up first by default and are also available via a new CZone icon that appears in the Pages menu. The data is also available for custom instrument windows like the one shown at the bottom of the entry, and updated configurations are loaded at the next boot up.

Doug, I think you have to configure any CZone module. If nothing else, the Meter module has to be told what its inputs are and I suspect that any shunt, even CZone's own, may need calibration.

Posted by: Ben in reply to Taniwha at May 10, 2013 12:08 PM | Reply

Thanks makes sense, Ben. Our B&G Zeus Touch is shipping to us right now, which is why I'm not au fait with the details of the integration. I read the manual and didn't see any mention of configuration, but mostly it just says "see the Czone documentation".

I absolutely agree with you that anyone seriously looking at a Czone installation should ante up for the USB interface - makes configuration and changes so much easier.

I've enhanced my configuration considerably since the first iteration as I learn more about the capabilities (or just want to try something out): I'm on version 6.3 of my config tinkering (I apply a software style numbering to keep track of all the changes properly).


Posted by: Taniwha at May 11, 2013 12:30 AM | Reply

Could I use my Actisense NGT-1 NMEA2000 gateway to access Czone modules?
Would I just need the software then?
Would Czone supply just software?
I have Simrad NSE's on board I can use as displays.

Posted by: peter c at May 11, 2013 10:23 PM | Reply

Hi Peter,

Apparently you can' use the Actisense gateway. I asked that when I bought my first Czone stuff 3 years ago. I don't know why (maybe Ben can supply the answer?).

At the time they said the only other USB interface that would work was the Simnet one. Maybe others also work now, but I wouldn't put money on it.

3 years ago BEP gave the software to me through a link in an email to a download page (I finally found that first email with the link - it was from Apr 2010). They didn't charge for that. So I assume that if you buy some Czone components today you'll still get the software link for free.


Posted by: Taniwha at May 11, 2013 11:42 PM | Reply

Thanks for all the info,Paul,much appreciated.
I plan on buying an interface module and USB/SW to play with.(self training)

Posted by: peter c at May 12, 2013 9:31 AM | Reply

Sorry - I just saw my previous post. Typo in the first sentence - it should read "you can't use the Actisense gateway". Got the apostrophe but missed the "t". My apologies if it caused any confusion.


Posted by: Taniwha at May 12, 2013 10:14 AM | Reply

I have been perusing the Czone product line in the Bep catalog.
The AC systems are way overkill for the size of boats I work on.I wonder if Bep is planning to expand the product line to cover something like a 30amp 120volt single inlet with 15 amp branch circuits.

Posted by: peter c at May 12, 2013 11:51 AM | Reply

I came to the same conclusion about the AC switches - definitely not needed for our 46ft sailing yacht. So we have a mostly traditional AC system not using Czone.

They introduced the AC a few years after the DC, but I haven't seen any indication that they'll put out smaller systems. It may be that to get the Czone style benefits with AC they need to be that big.

Clearly aimed at large power boats with many AC circuits.


Posted by: Taniwha at May 12, 2013 9:00 PM | Reply

I recently read that proprietary PGNs are the lowest priority on N2k. In a distributed power system, any latency issues are likely to go unnoticed. Is there any concern out there about more time sensitive data going over proprietary PGNs. It seems the "open" N2k standard is seeing more manufacturers deploy proprietary PGNs. How will that effect the quality of data on the bus...

Posted by: Eric at May 23, 2013 9:40 AM | Reply

Hi Eric, I believe it's true that proprietary PGNs have the lowest priority and I think it's the right way to go. I certainly want developers to be able to create functionality faster than NMEA writes standards, but I also like the idea of incentives to make new ideas standard.

But I'm not seeing issues with proprietary PGN latency. Since early on my trip north I've had both of Gizmo's N2K networks bridged (with a simple BEP product) and so all the screens and sensors you see in recent entries are all on the same bus. That means something like six GPS receivers and two forms of digital switching, Maretron's and BEP's.

Various diagnostics indicate that the bus is only working at about 25% capacity and I've never seen a delay or mistake in switching. Not to say there haven't been issues, but it's oddball stuff like miscalculation of headings because devices apparently get confused by multiple variation sources. I look forward to the Mystic Valley smart bridge which will let me filter which PGNs cross over.

Incidentally, the N2K Power PGNs are now official:

But I'm not sure that any company is using them yet, and there may be reluctance. N2K has supported ultra high priority engine commands almost since inception but that hasn't meant that the engine manufacturers jumped onboard.

I also recently learned that no BEP CZone product has yet received NMEA 2000 certification, even though BEP was one of the first to work on the power standards. I'm disappointed about this and hope they fix it, but I also think that seeing so many builders go with CZone -- a wicked big decision -- should trouble NMEA in terms of how highly certification is respected.

Posted by: Ben in reply to Eric at May 23, 2013 10:13 AM | Reply

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