Tech TipAs you will see from the instructions below using the dipswitches is not that easy. If after reading the instructions you give up and buy the computer interface instead you won't be the first to do so. Using these dipswitches is rather challenging and only real application in my mind is when you are stuck away from civilization and need a quick fix. For any other situations I suggest you hook the multiplus up to a computer. Its so easy and you will thank me!
Programming with the built in dipswitches doesnt require any extra equipment, but is not a very intuitive proceedure and its hard to know if you have done it correctly. For those with perseverence, it is however possible and my example below demonstrates the proceedure for making some basic adjustments. First lets look at the default settings for the Multiplus as it comes out of the box. I am referring the the US version of the 12/3000 MultiPlus. This comes from the Service Manual
If you refer directly to the Service Manual it goes into an explanation of what the settings mean, I wont repeat it here. I am only going to try and demonstrate how to adjust three settings, the AC Current Limit, the Battery Type and the UPS function as these are the functions that in my experience might be most useful to adjust in the field without a computer. Lets look at the dipswitches themselves first:
The dipswitches are in the top left corner, numbered 1 through 8, with 1 on the bottom and 8 on the top, "on" to the left and "off" to the right, as supplied they are all "off". Also circled are the two push buttons associated with these switches. The dipswitches by themselves don't do anything until you save the settings with the push buttons.
To program the Multi with the dipswitches you need to disconnect the shorepower and have the inverter on and running on battery power, preferably under no load. As you now have the cover off the circuits are live and you need to be careful to not touch any live parts. Its best to do this with some non-conductive stylus.
Here comes the tricky part, I hope you are paying attention: Each dipswitch has two programming functions, one from Step One, and one from Step Two.
- Step One programming includes the settings for limiting charge current, and for limiting AC input and some other items. You set the dipswitches and then push the UP button (top button circled in the picture above) for two seconds to save the settings. For our example we are going to change the AC Current Limit from the default 50 Amps to 30 Amps. This will prevent you from blowing the dock circuit breaker when you connect to a 30 Amp dock service.
- Step Two programming includes the Battery Type and UPS settings we want to adjust for our example as well as some other settings we are not going to change. We set these dipswitches as we want, push the DOWN button for two seconds to save the settings. Then we can leave the switches where they are or turn them to off, it doesnt matter.
When we push the save button we are saving all the settings including the ones we are not interested in, so we cant avoid dealing with all the settings.
STEP ONE SETTING
Here is what the Step One settings look like when you start. You can see that the top three dipswitches are reserved for AC input, the next for AES (Automatic Econony Switch), the next two for Charge Current and the last two for Stand Alone Mode. The only one we want to change for our example is the AC Input. We are going to change it from 50 Amps, which is the default, to 30 Amps, because our example boat has a 30 Amp power supply. Next we refer to the manual to see what arrangement of dipswitches corresponds to 30 Amps.
This tells us that to set up for 30 Amp shorepower limit we need to set Switch 8 to on, Switch 7 to on and Switch 6 to off.
We arent finished here however because even though we dont want to do anything with the other settings of Step One we still want to make sure we are leaving them in their default settings. By referring to the default settings we can see that the next dipswitch, #5 for AES, the default is off because AES is by default off.
The next two switches (#3 and #4) are for Charge Current and by reference to the default settings at the top of this article you can see that the default is 75% of the maximum
So here we see that even though we want to leave a setting at its default we still have to fiddle with its dipswitches. To set the charge current to the default 75% switch #4 has to be on and switch #3 has to be off.
The last two switches are for Stand Alone mode and are not used in step one, so leave them to off. Here is what our dipswitches are going to look at when we are finished:
To save these settings push the top button for two seconds as shown below:
The two UPPER right hand red lights will flash to indicate the settings have been accepted for Stage One. Once you have saved the settings you can set all the switches back to OFF and start into STEP 2
STEP TWO SETTING
Here are the functions of the switches for Step Two:
The top two switches deal with Battery Type and Charge Voltage and they are ones we want to adjust. We also want to adjust Switch #3 the UPS function. But as before we can't avoid addressing all the switches because we have to save all the settings at once.
For battery type settings there are four choices and lets say for our example we want to choose the one with the lowest charge voltage because we are using some rather sensitive Gel batteries, here is an excerpt from the manual
In this example it is telling us that for the highlighted battery type we need to have dipswitches 7 and 8 set to off.
Then to set our UPS function to "off" we need to adjust dipswitch #3 to "off". (The UPS function sometimes causes trouble with small generators and turning it off usually clears up the problem)
So to change our two settings we had to adjust three of the dipswitches to "off". We still have to make sure the other dipswitches reflect the default values.
Switch 1 would be set to "off" meaning 60 Hz
Switch 2 would be set to "off" meaning 120 Volts
Switch 3 we have already set to "off" to turn the UPS function off
Switch 4 would be set to "off" meaning dynamic current limiter is inactive
Switch 5 Adaptive charging characteristic would be "on" (meaning four stage charge curve)
Switch 6 Absorption time "on" meaning 8 hours
Switches 7 and 8 we have already set for our battery type.
At the end our dipswitches would look like this:
When we are finished we push the Down button for two seconds to save the settings.
Thats it, you are done, The two LOWER right hand red lights will flash to indicate the settings have been accepted for Stage Two. . I would suggest checking to see if it worked. Check the voltage ouput and frequency when inverting, check the charge voltage when charging and check in particular that whatever settings you adjusted ended up being what you intended. As you saw its rather complicated so dont just assume you did it right, check and verify.
And remember that if you have access to a Mk3USB interface and a computer you can do all this and more with considerably less pain. How to do that will be the subject of my next Blog Post.
I did the excercise described above after I wrote about it. Its a lot easier to do than it is to write about it. The whole operation takes less than a minute. I had the Multi hooked up with a computer interface at the same time so I was able to check on the computer if my settings had been succesfully adjusted. It worked fine for the UPS function and the Charge Voltage function but I didnt have as much luck with the Current Limiting function. It did adjust the values but not in the way I expected. Maybe the manual is a bit out of date, I dont know, I will have to check with the folks at Victron.
Easy? Not Easy? Please leave your questions and comments below.