# Help with SPD recommendation. (Other suggestions or tips welcome too!)

**URL:** <https://community.victronenergy.com/t/help-with-spd-recommendation-other-suggestions-or-tips-welcome-too/63349>\
**Category:** DIY\
**Tags:** rv, cerbo\_gx, multiplus, mppt\_controllers, offgrid, diy, cerbo-gx\
**Created:** [29 September 2026 21:59 UTC](https://community.victronenergy.com/t/help-with-spd-recommendation-other-suggestions-or-tips-welcome-too/63349 "2026-09-29T21:59:52Z")\
**Posts on this page:** 3\
**Page:** 1

<div class="post-metadata">

**Author:** ![Turfnsurf](https://avatars.discourse-cdn.com/v4/letter/t/6f9a4e/32.png) [@Turfnsurf](https://community.victronenergy.com/u/Turfnsurf)\
**Post date:** [29 September 2026 21:59 UTC](https://community.victronenergy.com/t/help-with-spd-recommendation-other-suggestions-or-tips-welcome-too/63349/1 "2026-09-29T21:59:52Z")

</div>

Warning - new forum member!

I’m in process of installing a 12V solar, LiFePO4 system to power a new 12V AC/Heat pump and allow charging of e-Bikes while boondocking across the US in my Lance Truck camper that sits on a Ford F250. I designed the electrical system using AI, which has made numerous mistakes in the process and I am a total newbie, so I sometimes don’t know a mistake when I see one. (I’ve uploaded the AI documents to provide more details if needed.)

[02-Lance915\_Master\_Cable Schedule.pdf](https://community.victronenergy.com/uploads/short-url/jXs9EZnxQshpIvj6sM5Vbjj231F.pdf) (286.7 KB)

I’ve got (6) 100W Callsun PV panels in (2) 300W strings, each connected to Midnite solar breakers that feed into separate SmartSolar 150/35. Other Victron devices in my install include a Cerbo GX MK2 with a touch 50, a Smart Shunt 500A, and a MultiPlus 12/2000/80. While reading a post on this forum I read about lightning protection which I hadn’t previously considered, and I’m curious what other boon-docking folks are using to protect their Victron equipment against surges.

And if any experts would be kind enough to point out any concerns or recommendations, I would greatly appreciate it 😀

[09-09-26 Lance915\_Master\_Diagram\_Printable.pdf](https://community.victronenergy.com/uploads/short-url/f2aWZUOlfSNFPuqlnTqQRHRdVZI.pdf) (218.1 KB)

---

<div class="post-metadata">

**Author:** ![Brucey](https://avatars.discourse-cdn.com/v4/letter/b/ccd318/32.png) [@Brucey](https://community.victronenergy.com/u/Brucey)\
**Post date:** [30 September 2026 01:43 UTC](https://community.victronenergy.com/t/help-with-spd-recommendation-other-suggestions-or-tips-welcome-too/63349/2 "2026-09-30T01:43:06Z")

</div>

Personally I would have a Midnite spd on each pv input (spd 115 or spd 300 dc depending on your array voltages), and then another on the ac input 300-AC (to protect against surges while connected to grid).

Just be careful theres fake SPDs out usually has a yellow wire, make sure to buy from a legit Midnite dealer.

---

<div class="post-metadata">

**Author:** ![Turfnsurf](https://avatars.discourse-cdn.com/v4/letter/t/6f9a4e/32.png) [@Turfnsurf](https://community.victronenergy.com/u/Turfnsurf)\
**Post date:** [30 September 2026 18:32 UTC](https://community.victronenergy.com/t/help-with-spd-recommendation-other-suggestions-or-tips-welcome-too/63349/3 "2026-09-30T18:32:39Z")

</div>

Thanks Brucey,

That’s what I was considering, but I don’t have much space for two of those at my breaker box or the cabinet that it’s mounted in. I could install them in the roof box where all my cabling enters the cabinet, but that would make the path to ground quite a bit longer.

And wouldn’t the 12V Air Conditioning unit require the same type of protection with their 15’ long 5AWG cables?