diy solar

diy solar

Some pictures from my boat upgrade

Monitoring and Control Questions:
I am starting to realize that some of the Victron equipment adds up in cost and the monitoring part is quite large. It looks like the REC BMS has is own PC monitoring software which uses a certain cable and Wakespeed has a bluetooth app. I expect this software simply shows battery SOC and cells with no history or indication of charging sources etc and the Wakespeed app sets up the parameters.

So I thought that initially as well, then I started adding up all the bits and pieces, and the cost differential was a lot lower than it looks like on paper, and it's something that "just works" with no muss or fuss. The cerbo gives you 3x VE.Direct, the equivalent of a MK3-USB (for the VE.Bus equipment) two CAN Bus interfaces, 2 dry contact relay controls, 4 tank inputs, 4 temperature inputs, and 4 digital outputs. All of it packaged into a nice rugged compact case that just works(tm). To get equivalent functionality out of a Raspberry Pi would be a lot messier and really not that much cheaper, especially if you factor in the cost of the time it would take to put all of it together.
Using available device software I think you would need Victron Connect on your phone or PC, using Bluetooth for Solar and DC-DC Charger. The Wakespeed bluetooth app is separate and so is the Rec software. Perhaps a couple of smartshunts using Victron Connect with bluetooth would complete the monitering. If this system can be used effectively, it would be less expensive, but I kind wonder about having so many separate apps.

In my integrated system, I only needed the relevant bits of software (Wakespeed and REC) for the initial configuration. After that, it's all monitored through the Victron system, and online through VRM. I'm sitting here at home on my couch, and I can quickly check on my boat, not just the power system, but also bilge levels, fuel level, and in the future the levels on my potable water and holding tanks. I can also remotely turn my inverter/charger off, so the day before I head out, I can kick the system out of "storage mode", fully charge my batteries, and have a tank of hot water for that night.

Using Victron there is also an inexpensive Raspberry_pi alternative which requires: a compatible touch screen, Victron Energy VE.Direct to USB Interface ($25) using Victron OS (opensource software) to connect the Victron SmartShunt 500A ($125) and other Victron devices with VE.Direct. This would eliminate need to purchase of Victron Cerbo GX ($340) and GXtouch 50 ($200) Screen (GX product range). I'd like to monitor the energy flow between:

You'll also need a CANBus inteface to talk to the REC and Wakespeed, you'll need a power adapter to go from 14V to the raspberry pi, you'll want a touchscreen for the raspberry pi, a case to hold it all.

  1. Wakespeed WS500 - how can the Canbus information be accessed?
Yes, new version of both the Victron software and the Wakespeed firmware allow monitoring of the alternator from within VenusOS.
  1. REC BMS LFP Battery - how can the Canbus information be accessed? Add a Smartshunt too?

Connected via CAN Bus, it just shows up as a battery fully integrated into the Victron ecosystem. I have a smart shunt in my system because I'm an instrument geek, and had the money to add it as a toy. It monitors the power drawn by my DC house loads.

  1. (2) SmartSolar 75/15 - Bluetooth app and via VE.Direct port
I pretty much never use the bluetooth app, I probably could have gone with the BlueSolar product instead and saved myself the $35
  1. Orion TR Smart DC-DC 12/12 30 - Bluetooth app only, Victron Connect does no show current in or out
In my case, I can remotely control it with the relay outputs from my victron system. It would be nice if there was VE.Direct, but there isn't.
  1. SFA Battery (perhaps) - add a Smartshunt?
My monitoring of the starter battery is largely complete overkill, it spends its entire life on the float. I mostly use it because I won an auction that I didn't expect to.
  1. The difference is that there would be $29 VE.Direct to USB cables running all over, rather than using Bluetooth or Wifi.
It's also a lot messier, takes up more room, and faces potential reliability options. It's definitely a way to go, but I'd rather just spend the extra $300 or so to go with the off-the-shelf product.
 
So I thought that initially as well, then I started adding up all the bits and pieces, and the cost differential was a lot lower than it looks like on paper, and it's something that "just works" with no muss or fuss. The cerbo gives you 3x VE.Direct, the equivalent of a MK3-USB (for the VE.Bus equipment) two CAN Bus interfaces, 2 dry contact relay controls, 4 tank inputs, 4 temperature inputs, and 4 digital outputs. All of it packaged into a nice rugged compact case that just works(tm). To get equivalent functionality out of a Raspberry Pi would be a lot messier and really not that much cheaper, especially if you factor in the cost of the time it would take to put all of it together.


In my integrated system, I only needed the relevant bits of software (Wakespeed and REC) for the initial configuration. After that, it's all monitored through the Victron system, and online through VRM. I'm sitting here at home on my couch, and I can quickly check on my boat, not just the power system, but also bilge levels, fuel level, and in the future the levels on my potable water and holding tanks. I can also remotely turn my inverter/charger off, so the day before I head out, I can kick the system out of "storage mode", fully charge my batteries, and have a tank of hot water for that night.



You'll also need a CANBus inteface to talk to the REC and Wakespeed, you'll need a power adapter to go from 14V to the raspberry pi, you'll want a touchscreen for the raspberry pi, a case to hold it all.


Yes, new version of both the Victron software and the Wakespeed firmware allow monitoring of the alternator from within VenusOS.


Connected via CAN Bus, it just shows up as a battery fully integrated into the Victron ecosystem. I have a smart shunt in my system because I'm an instrument geek, and had the money to add it as a toy. It monitors the power drawn by my DC house loads.


I pretty much never use the bluetooth app, I probably could have gone with the BlueSolar product instead and saved myself the $35

In my case, I can remotely control it with the relay outputs from my victron system. It would be nice if there was VE.Direct, but there isn't.

My monitoring of the starter battery is largely complete overkill, it spends its entire life on the float. I mostly use it because I won an auction that I didn't expect to.

It's also a lot messier, takes up more room, and faces potential reliability options. It's definitely a way to go, but I'd rather just spend the extra $300 or so to go with the off-the-shelf product.
Good points, and I can gain access to it via:
  • Victron Remote Management (VRM) portal with wifi or tele sim card
  • Access directly with GX Touch 50 or MFD
  • VictronConnect app via Bluetooth capability.
And more reliable, fewer wires and less time.
 
Good points, and I can gain access to it via:
  • Victron Remote Management (VRM) portal with wifi or tele sim card
  • Access directly with GX Touch 50 or MFD
  • VictronConnect app via Bluetooth capability.
And more reliable, fewer wires and less time.
Just be aware that LTE etc... does require an external router. I have a Netgear MR1100 to operate the wifi network on my boat (which also connects to my AIS (Vesper XB8000), our iDevices (For both NMEA data for charting, and SignalK for working on boat instruments), and provides the link to VRM.
 
Thanks svsagres that would be very helpful. Rather than mess up your thread, I decided to pose a slightly different schematic (very rough), but much of it would be similar to your refined setup. Your thoughts would be appreciated.

Monitoring and Control Questions:
I am starting to realize that some of the Victron equipment adds up in cost and the monitoring part is quite large. It looks like the REC BMS has is own PC monitoring software which uses a certain cable and Wakespeed has a bluetooth app. I expect this software simply shows battery SOC and cells with no history or indication of charging sources etc and the Wakespeed app sets up the parameters.

Using available device software I think you would need Victron Connect on your phone or PC, using Bluetooth for Solar and DC-DC Charger. The Wakespeed bluetooth app is separate and so is the Rec software. Perhaps a couple of smartshunts using Victron Connect with bluetooth would complete the monitering. If this system can be used effectively, it would be less expensive, but I kind wonder about having so many separate apps.

Using Victron there is also an inexpensive Raspberry_pi alternative which requires: a compatible touch screen, Victron Energy VE.Direct to USB Interface ($25) using Victron OS (opensource software) to connect the Victron SmartShunt 500A ($125) and other Victron devices with VE.Direct. This would eliminate need to purchase of Victron Cerbo GX ($340) and GXtouch 50 ($200) Screen (GX product range). I'd like to monitor the energy flow between:
  1. Wakespeed WS500 - how can the Canbus information be accessed?
  2. REC BMS LFP Battery - how can the Canbus information be accessed? Add a Smartshunt too?
  3. (2) SmartSolar 75/15 - Bluetooth app and via VE.Direct port
  4. Orion TR Smart DC-DC 12/12 30 - Bluetooth app only, Victron Connect does no show current in or out.
  5. SFA Battery (perhaps) - add a Smartshunt?
The difference is that there would be $29 VE.Direct to USB cables running all over, rather than using Bluetooth or Wifi.
svagres advised that the rpi solution, while an appealing alternative, is actually more costly in time and effort, and is not "off the shelf" so will require tinkering.
 
I’ll try to knock together a little diagram of the FET circuit tonight.
I would really appreciate your diagram. Due to Goboatingnow comments in my thread, regarding having an advanced disconnect alarm/or relay, I think the best way to go is to use the REC BMS and a 7713 relay switch interlocked with the Wakespeed WS500. So I will need to know how to wire it. Thanks.
 
I would really appreciate your diagram. Due to Goboatingnow comments in my thread, regarding having an advanced disconnect alarm/or relay, I think the best way to go is to use the REC BMS and a 7713 relay switch interlocked with the Wakespeed WS500. So I will need to know how to wire it. Thanks.
Here it is:

7713 Control Circuit.png

The circuit assumes you're using the REC Pre-charge circuit box, rather than just having the REC control the 7713 directly. If you don't have an inverter with big capacitors (such as the 2kVA Multiplus) you don't need either of these (the pre-charge or the above circuit). On the pre-charge box, the Contactor+ terminal is just wired through to the line voltage, so that is a good place to get the power for the transistor. In turn, when the pre-charge closes the contactor, it connects the Contactor- terminal to the -ve bus, which in turn, turns on the P-FET. This connects the Control Line on the 7713 to +12V, which causes contactor to close. The 120k ohm resistor is just there to bias the transistor and pull it up so that everything behaves properly. Exact resistance isn't critical, I just picked it nice and big so that effectively no current flows through it.

The choice of the transistor isn't critical either, as long as it's a P-FET, and has a sufficiently high enough voltage rating.
 
Svsagres. Thankyou. I did not realize that this circuit and the precharge are used when a multiplus is used.

If you don't have an inverter with big capacitors (such as the 2kVA Multiplus) you don't need either of these (the pre-charge or the above circuit).

Since I will just have a small 120vac 15a charger, I won't need the circuit or the precharger. Sorry for the misunderstanding.
 
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In my setup, it’s extremely unlikely for the BMS to ever open the 7713 on its own without warning. The BMS is managing all the the charging over CAN. If a call starts going high, it will order the current limit down to something like 2A to let the active ballancer do its thing. We’ve been running the system for 3 months, using the full battery capacity, and the system has never operated the relays except when we’ve deliberately exercised it. The BMS is in full control of the charging system, if the rest of the charging system loses contact with the BMS, it goes into a safe mode.

If the WS500 stops receiving CAN messages, it will drop into “limp” mode, setting its voltage limit to 13.2v, which is pretty safe.

I’ll try to knock together a little diagram of the FET circuit tonight.
this is the way to do things
 
Svsagres. Thankyou. I did not realize that this circuit and the precharge are used when a multiplus is used.



Since I will just have a small 120vac 15a charger, I won't need the circuit or the precharger. Sorry for the misunderstanding.
whats a precharger, do you mean a low current charger for a potential pre-qualifying charge ?
 
having used VE.smart ( bluetooth ) networking, its grand if you stay within a small set of victron gear. The big issue is its a closed protocol and hence a BMS cant "get at it " ( unless Victron release one)

This leaves you with a home brew using Ve.direct , or a Cerbo/Venus system using ve.can, ve.direct etc etc depending on the mix of kit , great system but very complex and a steep learning curve as well as added expense

in my view the first stage of a centrally controlled system is remote charge stop start , victron MPPT units have a remote input line as does the Wakespeed and mains chargers can just be disconnected by relay . This would allow a BMS to at least dictate charge start and stop strategies without CAN buses etc

the whole area is ripe from a range of NMEA 2000 compatible charge components systems linked together
 
having used VE.smart ( bluetooth ) networking, its grand if you stay within a small set of victron gear. The big issue is its a closed protocol and hence a BMS cant "get at it " ( unless Victron release one)

This leaves you with a home brew using Ve.direct , or a Cerbo/Venus system using ve.can, ve.direct etc etc depending on the mix of kit , great system but very complex and a steep learning curve as well as added expense

in my view the first stage of a centrally controlled system is remote charge stop start , victron MPPT units have a remote input line as does the Wakespeed and mains chargers can just be disconnected by relay . This would allow a BMS to at least dictate charge start and stop strategies without CAN buses etc

the whole area is ripe from a range of NMEA 2000 compatible charge components systems linked together
The cerbo system is pretty much plug 'n play. The REC folks have already done the work to make it talk to the cerbo, and all you have to do is plug in the VE.Direct stuff and it just magically works. All I had to do was set the REC for the correct CAN bitrate (250kbps) plug it in, along with the MPPT and MultiPlus, and it all started talking without an intervention. That's bridging VE.Direct (MPPT), VE.Bus (Multiplus) and VE.CAN (REC BMS + Wakespeed). Yeah, it's $600 or so for the cerbo + display, but the remote monitoring and interoperability is definitely worthwhile. Especially if you get into some of the automation bits provided by SignalK and Node-Red.
 
@svsagres thanks for advising about your experience with Cerbo.

@Goboatingnow wrote:
in my view the first stage of a centrally controlled system is remote charge stop start
  • victron MPPT units have a remote input line
  • as does the Wakespeed
  • and mains chargers can just be disconnected by relay .
This would allow a BMS to at least dictate charge start and stop strategies without CAN buses etc
So using the REC BMS interrupts would we be able to wire this up, without using a Victron CerboGX or GXtouch50?
 
@svsagres thanks for advising about your experience with Cerbo.

@Goboatingnow wrote:

So using the REC BMS interrupts would we be able to wire this up, without using a Victron CerboGX or GXtouch50?
The Wakespeed will get its direction directly from the REC via canbus. No need for the cerbo there. However, without the Cerbo your MPPTs will be operating blindly based on voltage alone. You also lose all the remote monitoring, and other integration capabilities. It’s up to you as to whether this is worthwhile.
 
@svsagres Good point. Do you know if a smartshunt wired to the MPPT's give them current?

The RECBMS -Wakespeed Canbus harness is only about $35, so that's simple.

"You also lose all the remote monitoring, and other integration capabilities."
Of course these would be very nice to have,
But could be added later, if we can configure the basic functions needed.
 
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@svsagres Good point. Do you know if a smartshunt wired to the MPPT's give them current?
Not directly. It might work with the VE.Smart Bluetooth stuff, but at that point you’re effectively doubling up your bms. But the smartshunt isn’t going to know when the bms wants to taper the charge, or change chargers voltages and they like.

You don’t strictly need the gxtouch, you can remote admin a cerbo over wifi from a smart phone. It’s just a real “nice to have”
 
The cerbo system is pretty much plug 'n play. The REC folks have already done the work to make it talk to the cerbo, and all you have to do is plug in the VE.Direct stuff and it just magically works. All I had to do was set the REC for the correct CAN bitrate (250kbps) plug it in, along with the MPPT and MultiPlus, and it all started talking without an intervention. That's bridging VE.Direct (MPPT), VE.Bus (Multiplus) and VE.CAN (REC BMS + Wakespeed). Yeah, it's $600 or so for the cerbo + display, but the remote monitoring and interoperability is definitely worthwhile. Especially if you get into some of the automation bits provided by SignalK and Node-Red.
I am playing with the VenusOS setup on s Pi , thats my route as the software can be extended to include other devices to monitor ( tanks , etc) I have a suite of LIN bus sensors so I'm writing a dbus extension for the Venus OS to handle that
 
I am playing with the VenusOS setup on s Pi , thats my route as the software can be extended to include other devices to monitor ( tanks , etc) I have a suite of LIN bus sensors so I'm writing a dbus extension for the Venus OS to handle that
Yeah, that’s not a bad route. I‘m using enough of the interfaces, between the tank levels, VE.Direct ports, CAN ports, and the VE.Bus interface that by the time you add all the bits and bobs your pricing isn’t too far off, plus you’re sailing around with a science experiment rather than a cohesive box. For me, spending an extra few hundred dollars was worthwhile to avoid these headaches, and spending my time on something I don’t find all that interesting.
 
Yeah, that’s not a bad route. I‘m using enough of the interfaces, between the tank levels, VE.Direct ports, CAN ports, and the VE.Bus interface that by the time you add all the bits and bobs your pricing isn’t too far off, plus you’re sailing around with a science experiment rather than a cohesive box. For me, spending an extra few hundred dollars was worthwhile to avoid these headaches, and spending my time on something I don’t find all that interesting.
My boats have always been floating science projects. !!! ( or a spy trawler as my friends suggest)
 
The Black battery switch is a DC Disconnect for our MultiPlus II inverter/charger.
Sorry for re-opening the old thread, but I have a question regarding the manual disconnect of inverter/charger.
Why do you need it (as you already have smart disconnect + override with 7713)?
How do you handle pre-charge when manual switch is used?
 
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