Victron Multiplus-II 2*120V and Progressive Industries EMS-LCHD50

[Ozzie Cozzies]

I currently have a Progressive Industries electrical management system EMS-LCHW50 installed. I've recently bought a Victron MultiPlus-II 2*120 inverter/charger and about to install it shortly - along with other solar install items. I would have assumed the logical AC wiring would involve
* 50A shore power to EMS,
* EMS to transfer switch, and Generator (Onan5500) to transfer switch,
* Transfer switch to inverter/charger, and lastly
* Inverter charger to AC distribution panel.
My issue is that reading the PI operating and instruction manual for the EMS (https://www.progressiveindustries.ne...b8577bfb5a.pdf), it clearly states on page 3 "Never plug the EMS into an inverter". Also, the Victron MultiPlus-II manual (https://www.victronenergy.com/upload...30V-pdf-en.pdf) stipulates on page 14 that the AC-In "must be protected by a fuse or circuit breaker rated at 50A or less, etc....".
As I understand, the EMS protects against high/low voltages and surge protection currents(much greater than 50A). Although it is rated for 50Amps, what's the consensus on it protecting the I/C for currents slightly above 50A, and whether a fuse/CB is necessary.
Also, there were some previous issues back in 2019 with connecting the EMS to the Victron I/C. The I/C developed buzzing noises, but then Victron issued a firmware upgrade to rectify the problem - i assume the latest models have this upgrade. Has anyone had any experience/issues with connecting the PI EMS into a Victron MultiPlus?

[rohrmann]

Not knowing much about solar installs, but why would you need the EMS connected to the solar system. I think if you just have the EMS protecting your rig from incoming utility power, ahead of the transfer switch, you should be good. The utility power is what is usually associated with lightning strikes, low and high voltage and all the other things the EMS protects against.

[Lee-CI]

Bob - the Victron Multi-Plus II ties directly into incoming shore power. OP is installing a Inverter that is also a Converter. The unit is designed to supply supplemental amperage from the battery side if one hooks up to 30a or 15a in cases such as mooch docking. i.e. power sharing supplied by the inverter when needed for full 50a service



OP - I would get with PI to get a ruling for the statement "Never plug EMS into an inverter". I'm going to be doing the same thing via a Surge Guard EMS.
The 50a requirement for a breaker on the input side of the Victron will normally be provided by the 50a breaker of the campsite power pedestal. One caveat to the proceeding statement is that a few places do not have breakers at the shore power pedestal. When getting disc brakes installed at the Cleveland county fairgrounds camping area in Norman, OK I was taken back by the fact that there was no circuit breaker where we hooked up shore power. We decided to have faith in our EMS to shut down incoming power if anything untoward happened. Two night stay, but we were glad to get back on the road to our next campsite.

Good luck with your install. Let us know how you come out and how you decided to set things up. Happy camping and safe travels

[rohrmann]

it clearly states on page 3 "Never plug the EMS into an inverter".



If that is what is required, then you should not plug an EMS into an inverter. I believe that means don't plug the EMS into the load side of an inverter, which would be the 120 volt output side, so an EMS on the incoming 120 volt shore power would not apply. The EMS looks backwards toward the source of the power, meaning the pedestal or other A/C power source. There is no way they could prevent you from having a protective device on a source of power.

[1wayhighway]

As I understand the instructions, and the statement, the EMS should never be fed from an AC source derived from an invertor, it must be plugged into a utility source or possibly a generator is acceptable.

The second question I believe the instructions are stating that the AC feed to the Victron must be protected by some means, either a breaker or fuse.

My 2 cents.

[bcrvman]

Originally Posted by Ozzie Cozzies

I currently have a Progressive Industries electrical management system EMS-LCHW50 installed. I've recently bought a Victron MultiPlus-II 2*120 inverter/charger and about to install it shortly - along with other solar install items. I would have assumed the logical AC wiring would involve
* 50A shore power to EMS,
* EMS to transfer switch, and Generator (Onan5500) to transfer switch,
* Transfer switch to inverter/charger, and lastly
* Inverter charger to AC distribution panel.
My issue is that reading the PI operating and instruction manual for the EMS (https://www.progressiveindustries.ne...b8577bfb5a.pdf), it clearly states on page 3 "Never plug the EMS into an inverter". Also, the Victron MultiPlus-II manual (https://www.victronenergy.com/upload...30V-pdf-en.pdf) stipulates on page 14 that the AC-In "must be protected by a fuse or circuit breaker rated at 50A or less, etc....".
As I understand, the EMS protects against high/low voltages and surge protection currents(much greater than 50A). Although it is rated for 50Amps, what's the consensus on it protecting the I/C for currents slightly above 50A, and whether a fuse/CB is necessary.
Also, there were some previous issues back in 2019 with connecting the EMS to the Victron I/C. The I/C developed buzzing noises, but then Victron issued a firmware upgrade to rectify the problem - i assume the latest models have this upgrade. Has anyone had any experience/issues with connecting the PI EMS into a Victron MultiPlus?

The EMS connected as you state is correct, it is NOT plugged into the inverter, it is plugged in to shore power. The EMS OUTPUT goes to the inverter. Countless RVers using the several brands of EMS available regularly connect them between shore power and the RV power cord.