Cell modem replacement & simple boat status monitoring leads

[MVCalypso]

Hi, hoping to tap the collective group experience base -

Context:
For years I’ve used a Netcomm 4G LTE modem onboard (a NWL-25-02, desc is at https://support.netcommwireless.com...680f60bb3bbd?Product=NWL-25-02-Spec-Sheet.pdf if anyone is curious). It’s configured as a bridge to be a 4G to Ethernet modem. It also has router functions etc. which are unused (the boat has a separate router after it to handle an onboard network).

The Netcomm box provides two sets of functionalities I would like to replace:

Data connection.

This is the basic cell service to Ethernet modem functionality. Box has a Sim card and I pay for a service plan for it.

External input event notification.

The box has a couple of DC sensor inputs for which you can configure input voltage trigger ranges etc. The box alerts (via text and/or email using the cell connection) if the inputs meet the trigger conditions. Currently I use this to alert me of a) Shore power drops/returns and b) house bank low voltage.

In contrast, the box’s usual router features are of little value to me. If a new box has them and they can be bypassed, to create a bridge/modem mode, that’s OK. A concern is that a fully featured box tends to be priced to include the router (and other) features which are of little value to me – so price box price is a consideration.

The Netcomm box is reasonably compact (approx. 6”x4”x1”) and uses 12vdc power. I don’t have space for rack mount stuff and DC pwr is highly desirable (to avoid specific use inverters etc).

The problem:

The adoption of 5G has gotten to the point where LTE connectivity is no longer very good where I am (SF bay area).

So, I've started to look around for a 5G replacement modem.

My first stop was to look up current Netcomm widgets… Alas, over the years, Netcomm was purchased by a company who subsequently went bankrupt in 2024, and the product line is no more.

So, I have to look for a different brand/model replacement…

I haven’t seen anything that handles both the cell modem and input trigger functions. If anyone knows of a similar unicorn, I’d love to get a reference to it.

An approach?

I’m now thinking about splitting the Netcomm functionality into two parts:

A 5G modem.

Any pointers to a DC powered 5G modem would be appreciated.

Boar sensing thingies

I suspect this one could open a whole new Pandora’s box.

Despite my fondness for tech gadgets (an urge I’m suppressing), I neither need, nor want, a million inputs or a new dedicated phone monitoring app to play with. I prefer not to incur any subscription $ for doing this (beyond the cell service data plan). I don’t want to add sensors to every electrical connection on the boat and I don’t need 24/7 video streams with an AI subscription to tell me what’s in the video. ;-(

Just some simple inputs that would alert using the boat’s network to the Cell system data connection would be fine.

I’m thinking that alerts for Shore power status, DC battery bank (one bank is fine) status, and Bilge pump (1 or 2 pumps) running would handle 99% of my monitoring desires.

What are others using for simple types of monitoring?

P.S. I may be able to add good recommendations to my list to Santa… ;-)

 

[Diep]

We have been using this as a 5G modem with good results for the past 8 months. It has router capabilities you don't need. I'm not aware of any consumer-level devices that are strictly a cellular router but finding that was not a priority.

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Recently completed install of new Victron electrical components. They include free monitoring through their VRM portal. Seems pretty slick but I wouldn't advocate it unless you already had other components installed or were undertaking a more comprehensive electrical upgrade.

 

[READY]

Suggest you consider a victron CerboGX as it can handle a lot of different digital and analog inputs and provide switched outputs as well. Maybe adds more cost but will give you many options and designed for these purposes.

Then pick up any cellular enabled router. Examples would be peplink or Teltonica.or even use a home cellular router. I do that with a Verizon box that adds about $40 to my monthly bill and works great. Have used it from San Diego to SF Bay with no issues (near shore). Or perhaps just get a starlink mini at $249 plus fee of $5/ month if you just need low bandwidth for remote monitoring. Cheapest option of all. Can switch to a $50 plan which includes 50GB if you want to do limited streaming.

 

[GB42-424]

Suggest you consider a victron CerboGX as it can handle a lot of different digital and analog inputs and provide switched outputs as well. Maybe adds more cost but will give you many options and designed for these purposes.

Then pick up any cellular enabled router. Examples would be peplink or Teltonica.or even use a home cellular router. I do that with a Verizon box that adds about $40 to my monthly bill and works great. Have used it from San Diego to SF Bay with no issues (near shore). Or perhaps just get a starlink mini at $249 plus fee of $5/ month if you just need low bandwidth for remote monitoring. Cheapest option of all. Can switch to a $50 plan which includes 50GB if you want to do limited streaming.

I've used a Teltonica RUT240 for many years on the boat with zero issues. External antenna acts as cell-to-wifi bridge to keep my phones working when far from towers. Also sends TXT MSG when programmed conditions are met. Eventually will upgrade to a 5G unit, however if TXT MSGs is all you need, a few carriers offer IOT LTE plans for a very reasonable price.

 

[Jeff F]

Ive used a Sonim H500 for the last 8 months or so. It's 5g and worked well. Agree that there are 5g home routers as well that should work. It's powered by USB that I run off 12v.

 

[MVCalypso]

Hi,
Thanks to all for the inputs & suggestions. It sent me off to do some more detailed manual reading. Here's some of my thoughts after doing more reading.

"Gateways": All in one, physical& mac layers, run by an internal micro, with software for routing, DHCP, DNS, firewalls, wireless APs and a kitchen sink, all wrapped in a box: There are lots of these things around and I'm pretty familiar with their ilk (from many years of doing computer network stuff).

Driven by a desire not to modify the rest of the boat network, the ideal box would be a simple, single purpose "modem only" widget (literally a cell antenna to Ethernet jack box). Alas, it seems that's not considered "of value" these days (as companies want to play feature check off list and include all the other stuff too). If I have to, I'll strip back a gateway config to become a modem - but I'd prefer to avoid it if possible.

Victron Cerbo (several flavors):
I don't have any Victron stuff aboard so while I was vaguely aware of the Cerbo box, I really didn't know any details; not even that there is more than one flavor of Cerbo things. I went off and did a bit of familiarization.

Some of the IO capability might be of use, but the boxes seem mostly oriented toward being an interface with other Victron components. Getting a current overview of the cerbo boxes was interesting though.

Current impression is that Cerbo is prob not the right fit for my needs.

Starlink:
I'm familiar with Starlink, lots of friends have them on their boats.

My usage area is 90% SF bay and the Cailf delta. A few years ago, there were significant non-cell coverage dead zones in the delta. That made Starlink more attractive, but as 5G deployment has progressed, the cell coverage has filled in. Today cell coverage is not much of an issue (5G. 4G coverage is fading out). The other 10% of my usage is near coastal and that also gets covered pretty well via cell.

For price vs performance, I think Cell is still ahead of Starlink as Cell plans are roughly 1/2 the monthly starlink pricing (comparable data speeds etc).

What I've lost track of are the service plan details. Starlink changes them so frequently that I quit following them. That also created a feeling that the Starlink product package you purchased may, one morning, have morphed into something significantly different, with a new monthly pricing. Finally, I'll just say that I'm personally resistant to sending money toward Musk.

Peplink, teltonica etc
Started reading up on what the current product lines look like. Not up to speed enough to have narrowed products down to specific models yet. Still researching.

Sonim H500
Thanks for this reference.

This could be a good solution for the cell network connection. I got intrigued when I noticed that verizon has a deal on these where the device is $1/mo for 36 months. $36 is a pretty reasonable price for the hardware.

The box is a compact form factor. Has an enet jack (which is the universal interface to the wired net on the boat). No WiFi 6 or 7 AP with a porcupine like set of antennas (that I would not be using). Includes an internal GPS and can provide GPS NEMA data over the net. Internal battery battery power / back up and can be powered easily by ship DC. I grabbed the user manual and first pass looks like It can be configured as I'd like. I've got this on the initial short list.


Thanks again for the pointers, it's really useful have those to work from!