Victron inverter/chargers are known for their excellent input current control, allowing users to pull power from more places.
The Digital Multi Control 200/200A GX is a simple device that, when connected to a Multiplus or Quattro inverter/charger, allows the user to remotely view and adjust the input current and toggle between ON, OFF, and Charger Only mode.
The Digital Multi Control is rated for up to 200 amps, granting system control for small mobile systems with a single AC source, all the way up to large split-phase and three-phase systems with multiple AC sources. This article will discuss how the Digital MultiControl works and when you might use each mode.
Reduce AC input, Maximize System Performance
Most inverter chargers do not allow you to readily adjust the AC input current limit. Traditionally if you're turning down AC input, you're reducing AC output. This is where the magic of PowerAssist comes into play.
What is the PowerAssist Function?
In a nutshell, PowerAssist is a built-in feature that enables Victron inverter/chargers to supplement available AC power from an external source with additional power from your batteries. This function is particularly relevant when the external source's power output is insufficient for the load demand. The switchover between power sources is almost instantaneous, ensuring that connected appliances and electronics receive uninterrupted power, even when demand increases.
Let's look at an example of when you might use the Digital Multi Control. Let's say you're in a camper van plugged into a 15 amp service. You reduce your AC input current limit to 14 amps on the Digital Multi Control to prevent an external AC input circuit breaker from tripping. Then, you want to turn on the air conditioning unit which draws 20 amps. Because the load exceeds the AC input current limit, the MultiPlus/Quattro will start inverting in parallel with the external AC supply and will provide the extra current needed with energy from the battery.
The ability to adjust the AC input current limit with the Digital Multi Control is especially useful for marine and mobile power systems that must plug into various shore power sources with different amperage ratings. For example, campgrounds generally have three types of shore power: 15/20 Amp, 30 amp, and 50 amp services. The Digital Multi Control makes it easy to adjust the AC input current limit based on where you plug in for the night. Suppose you're running an extension cord from grandma's house. Most residential circuits are rated for 15 amps. Adjusting input from a Digital Multi Control can prevent the circuit breaker from tripping when the current limit is set properly.
One of Victron's more basic products, the Digital Multi Control offers great immediate value to the user, showing:
- If the inverter/charger is receiving power.
- What stage of charging the inverter is in (bulk, absorption, float).
- If the battery is very low or the battery temperature is too high.
A simple toggle switch gives users three modes: ON, OFF, and Charger Only.
When the MultiPlus is switched to ON with no grid connected, the inverter will supply the power. When the MultiPlus is switched to ON with a grid connection, the shore power will pass through the Digital Multi Control to power your AC loads as well as charge your batteries.
If the AC loads increase, the MultiPlus will decrease the charger output to compensate for the increased AC load. If the AC loads increase beyond what the shore power source is capable of, the MultiPlus will start to discharge the batteries to support the grid.
When the MultiPlus is connected to shore power with Charger Only enabled, the grid will power the loads and charge the battery. If we lose the grid, MultiPlus will not start inverting. This can be a useful way to protect your batteries in the case of a grid failure.
From the front display panel, LED indicator lights identify the current state of the MultiPlus and whether there is an alert (overload, low battery or a temperature).
Curious minds would like to know…
When should the Digital Multi Control be put in Charge Only mode?
If you are parked and plugged in for the night at a campground or RV park, put the Digital Multi Control in Charge Only mode. This will ensure that your batteries will not be drained if the AC source fails.
**Charge only mode will only supply power if there is an AC source available**
When should I have it in the ON position?
If you are plugged into shore and running larger loads that may need support, keep the Digital Multi Control in the ON position. The inverter will supply power to AC loads with or without a shore power source.
When should I turn it OFF?
Turn the Digital Multi Control OFF if the system is not in use or it is in storage. This is a good way to minimize standby loss.
When I adjust the AC input current limit on the dial, it stays the same on the display. What's wrong?
It's likely that the "Overruled By Remote" function is not programmed into the inverter charger. This feature needs to be enabled to allow the Digital Multi Control to make changes.
Can I set limits on the AC current setting?
Yes, you can program the Digital Multi Control to have a maximum available current limit. During the setup of the Digital Multi Control, you can set the maximum current limit anywhere from 1A to 200A. This is particularly useful if you're not always going to be the one running your system. Another example is if your shore power input port is rated for 30A with 10AWG wiring between the inlet and your Multiplus II - you can avoid a hazardous situation by setting your Digital Multi Control to a max available input level of 30A.
Can a Digital Multi Control be used in a Dual inverter setup?
Yes, the Digital Multi Control can be used in stand-alone, parallel, and 3-phase applications. Depending on the configuration, VE.Bus System Configurator may be required to program the inverter chargers. The Digital Multi Control can handle up to 200 amps. You may also control the current limit of multiple AC inputs, such as; AC In 1 and AC In 2 for the Quattro Inverter/Chargers, allowing you to set your shore power current and generator current separately. The DMC may control up to 4 independent AC inputs in complex systems.
Both models function in exactly the same way. The only difference is the mounting style. The Digital Multi Control 200/200A GX has a newer, hard plastic design with a mounting frame for a panel mount. An optional wall-mounted enclosure can be purchased to tidy up the installation. Unlike other Victron GX devices, such as the Cerbo GX and GlobalLink 520, the Digital Multi Control GX does not require any kind of firmware update.
As you can see, the Digital Multi Control is a simple product that provides the end user with a great deal of value. Feel free to reach out with questions.
