Solar setup with Sargent ec155

[Deanfitz82]

afternoon all just wondering if anyone has a few minutes spare if they could advise me on the diagram I’ve been working on I’ve read a few threads and hopefully I’ve learnt something new to all this any advice would be greatly appreciated

 

[roadtripper]

Just to save everyone's necks

 

[roadtripper]

So after a quick glance through things to think about:

• You don't show a DC-DC charger - if you are expecting the Sargent split charge relay to do the charging then think again, you'll likely wreck the Renogy batteries, your alternator, the Sargent or all three. LiFePo needs a dedicated charger that understands the voltages needed and can keep control of the excess currents that could flow with direct connection.
• Make really sure the Sargent mains charger is disabled - I think this EC system is fused to enable that but confirm with a multimeter
• Is there a reason for 2 100Ah batteries rather than choosing a single battery
• Your Durite isolator isn't isolating the batteries, they would still be connected to the Sargent and then all your existing electrics. There are views on isolators but if you want to put one in the main reason is to cut the connection to the battery completely.
• What is your inverter doing? Hopefully this provides alternative (clearly marked) 240v sockets and you are not trying to splice into the same mains wiring that comes from the Sargent - that would be highly dangerous
• If you have 2 banks of solar it's probably much simpler to have them on separate MPPT controllers rather than trying to juggle DC connects and expecting the MPPT to handle a mixed set of panels. Just have an Anderson type connector somewhere handy (and fused!) for them to plug into.

Fundamentally what are you trying to achieve? You mention it's a solar setup but you've also got new LiFePo batteries, a mains lithium charger, an inverter, no DC-DC charger... if any of those are existing items better to clearly say so, you've only mentioned the Sargent explicitly.

 

[Cool Carlos]

I've got/had a similar setup, now upgraded to the following ...

• Kept:
  • EC155 Sargent for DC distribution (essentially it's now a glorified bus bar and switches)
  • 2 x 100W Solar Panels
  • Removed the Sargent capability to charge the leisure battery (removed the fuse and as a double check ensure big red switch is kept off)
• Added:
  • Renogy 50A DC DC MPPT
  • Renogy 100Ah Smart Lithium Leisure Battery
  • Renogy One Core
  • Victron Smart Shunt
  • Victron Smart Battery Protect (probably overkill as the Lithium has a built in BMS)
  • PV Isolator (double pole)
  • Isolator switches for leisure battery, solar and starter battery
  • Piggy back fuse for ignition live feed
  • 300A Negative and Positive Bus bars
  • Rated cables throughout and lots of fuses (ANL, mini ANL, Midi & blade)
• Junked:
  • AGM 80Ah battery
  • Durite split charge (which was killing my AGM battery)

I did consider an inverter but not needed at the moment. Plans are that solar and DC/DC does a good job of keeping the leisure battery charged and therefore will charge the battery from EHU only when needed using 3 pin mains socket to Victron IP or Noco (still to decide which) rather than 'hardwire' in.