Friday, March 1, 2013

Victron Multi 3000 12vDC 120vAC 50A Setup

I wrote a while back about installing the Victron MultiPlus 3000 Inverter/Charger (the model that does 12v, 3KW, 120V@50A, 120A charger). It is a nice unit that can augment incoming shore power or generator power to start heavy loads like air compressors or air conditioning units. It fit in the space where the old Sentry battery charger lived, which is within two feet of the battery buss bars, minimizing loss in the DC cabling.
We bought our MultiPlus from Peter Kennedy Yacht Services in Annapolis, MD. It cost a bit more than buying it from a discount house, but I was able to get Peter's input on the system design as well as a local source for wire and parts for the installation. He also helped with crimping some of the large cables that I used to connect the Victron to the battery distribution buss bars. Configuring it to work with the Honda generator was a bit more challenging. The Victron manual translations to English don't easily communicate what is required. I thought it worth describing what I did to get it to augment the Honda generator in order to start and run our 16K BTU Cruise Air air conditioner.
One mistake I made was the selection of the BVM-600. I should have purchased the BVM-602, which allows monitoring of a starting battery voltage. I'll be swapping the 600 for a 602 in the near future.

Display Installation

Leopard 40 Stock DC Panel
When doing the initial MulttPlus install, I didn't have enough time to include installing the control panel or the BVM-600 battery monitor. I did get the BVM-600 shunt installed, so all that was left was to install the wiring and the display. The Leopard 40 has a very nice DC panel. I particularly like the battery monitor switch that allows checking any of the three batteries: House, Port Engine, Starboard Engine, and Off. The volt meter on LUX worked, but the amp meter didn't. I prefer a battery monitoring system that tells me the amount of charge used from the house bank as well as the voltages of the starting batteries.

I looked at the MultiPlus control panel and the BVM display and determined where to install them. I replaced the meters and the fresh water pump light with the new displays. I installed a yellow LED beside the fresh water pump switch to show pump activity. It isn't very bright, which is good at night, but doesn't draw attention during the day. I would also like to replace or augment the single bilge pump light with an array of 4 LEDs that show me which pump is running. It always bothers me when a pump runs and I don't know if it is the engine compartment pumps, which run regularly, or a cabin bilge pump, which should never run.
MultiPlus Control Panel

DC Panel Wiring Side

It took several hours to remove the old displays, lay down blue tape, mark the holes for the new displays, and cut the holes. I used a small board clamped to the panel as a backing guide for a hole saw to cut the BVM-600 mounting hole. It barely covers the hole of the voltage meter. I used a rotary tool (Dremel tool) and single-ended hacksaw to cut the hole for the MultiPlus control panel. It replaces the amp meter and fresh water pump indicator. Be patient when cutting. It takes a while with hand tools, but looks good when finished. The old wiring is wire-tied out of the way. I intend to use the battery voltage monitor selection switch in the future when I switch to the BVM-602.
Selector Switch for Second Battery Voltage Input

Update January 2014: I've switched to the BMV-602, which allows monitoring a house bank for voltage and current as well as a starting battery voltage (not current). Since there was already a rotary switch in the panel to allow selection of the battery voltage to monitor, I used its output to feed a new wire that extends to the shunt's secondary battery input. The wire in the center of the switch (tailing off to the upper left of the photo) is common and goes to the BMV-602 shunt secondary battery input. The other wires are as they originally were connected - one to each battery. When the BMV-602 is set to monitor VS (Voltage of Starting battery), I can use the rotary switch to select any of the three batteries and quickly see the voltage of any of the three. All the battery capacity and current measurements are done only on the house bank, because that's where the shunt is installed. This is not a problem because the starting batteries should not be deeply discharged and their voltage should be 12.6v or higher.

DC Panel With Displays Mounted
The panel looks very nice with the new displays mounted (see below).

The BVM-600 connects to the shunt with a straight-through RJ11 6-conductor cable. We had a problem in that it would not display the battery voltage. I checked the cable numerous times to make sure that it had no breaks or shorts. We had to tug on the wire a bit to get it through the conduit, so perhaps it is damaged in a way that isn't clear to me. Since I want to change it out for a 602, I'll try the new cable that comes with the 602. Update: It was a problem with the circuit board on the shunt.

The MultiPlus control connects to the MultiPlus 3000 with another RJ-45 cable. There are two RJ45 jacks on the MultiPlus 3000, one for the display, and another for the computer interface. There are a few parameters that can only be modified using the computer interface.


The manuals for the Victron equipment are available online. The programming software for the MultiPlus can also be downloaded.

The BVM-600 only needs the battery capacity set and the points at which you want to have an alarm sound. It is pretty easy and is clearly documented.

As background on the MultiPlus 3000 capability, there are some nice papers produced by Victron that describe augmenting an external power source.

When I initially tried the Honda with the A/C unit, the generator didn't go into overload. It looked like the Victron didn't go into overload either, which was puzzling. Wasn't it supposed to augment the incoming power source? The manual wasn't clear on how to make this work. So I exchanged emails with Ruurd ten Brink at Victron. My email to him:
I have just finished installation of a Multi 12v 3K. I have a Honda UE2000i that I connect to the shore power connector. The Multi sees it and shows 120v on the AC1 output. When I turn on the air conditioner (EnviroComfort 16K BTU), the generator never shows an overload, but the AC1 output is turned off shortly after the air conditioner starts. Since the Honda never shows an overload, it looks to me like the Multi is disabling the pass through of the shore power. I am suspecting either a low voltage threshold or a pass through current limit. Do you have any suggestions on things to check or settings to change? I have the MK2 USB and the Digital Multi Control, but have not connected them yet. The air conditioner is connected to the AC2 output so that it won't run when either the shore power or generator is not available. Are there limits on the AC2 output that would cause it to turn off when the air conditioner starts? I do not see either the Honda EU2000i overload or the Victron overload LED light.
His reply was brief, with an attached picture:
Take  care of this setting and I think this is solved
Specialy the UPS function of !!
MultiPlus Computer Programming Display
 The settings allow for variations in input frequency, disable the UPS option, enable the dynamic current limiter, and set the input current limit to 95% of the generator output. The Victron will augment the input power source when the load reaches 90% of this figure, as described in his reply to my request for clarification. His reply:

Power assist will only start after the max source ( shore or generator ) current is reached.
This means, with the generator running, you have to adjust ( in the software or with the panel ) the AC input amperes of the generator to ± 95 % of the maximum delivery capacity of the generator.
When the system has reached that limit ( 90 % of the generator supply ) the power assist will start.
Once I made the changes and set the AC input current limit to 12A, the Victron did what I wanted. I had the Honda set with Eco mode OFF, which makes it run a bit louder than with it enabled. I didn't try it with Eco enabled, though with the Victron, that may work as well.
The Honda 2000 was able to run the air conditioner after the Victron helped it start. There was even power left over for the Victron to go into charger mode and restore power to the batteries. One of the nice features of the Victron is that when input power is fully consumed by AC loads, it will reduce the charging function to avoid overloading the input power source. The MultiPlus control panel has a knob labeled "current limit", shown displaying "16" in the above picture, where the input current limit can be changed without using a computer. I have not looked at the instructions for using the dip switches in the Victron or the control panel to see if the above settings can be configured without the computer interface.

My remaining concern is that the manual says that the AC2 output is limited to 16A, while the AC1 output can handle up to 50A. The AC2 output is only enabled when input power is provided to the Victron, so that high capacity loads cannot pull down the battery accidentally. That is great, but why limit its output to 16A? That's not much output power. I wonder if the statement is a mis-translation.

During the installation and configuration, I made good use of the 'peak' function on my multimeter, a Craftsmen 73756 clamp-on AC/DC meter. It is a very valuable tool for working on boat electrical systems. I have a good set of alligator clip leads to go with it. I've sometimes setup a camera to record voltages or current while working on something so that I can see the result of something I'm doing.


I'm quite happy with how it worked out. It would be nice if Victron were to create a few "How To" documents on the use of their products. I showed the settings that they suggested, but don't have a clear understanding of what the settings really do. I would like to understand each setting so that I know when to use it and when to not use it.