multiplus_faq
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multiplus_faq [2017-06-21 12:45] – guystewart | multiplus_faq [2019-02-20 13:34] – [1.3 Minimum voltage levels] guy_stewart | ||
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- | What to do when a MultiPlus does not accept generator power | + | __What |
- | ---- | + | __ |
Power supply from a generator is typically more variable than a power supply from shore or the main grid. The MultiPlus is sensitive to this and will reject power that is outside of it's programmed settings causing the unit to not connect, synchronise or charge. | Power supply from a generator is typically more variable than a power supply from shore or the main grid. The MultiPlus is sensitive to this and will reject power that is outside of it's programmed settings causing the unit to not connect, synchronise or charge. | ||
+ | |||
+ | ==== Selecting a Generator ==== | ||
+ | |||
Some generators are more suitable than others for use with inverter/ | Some generators are more suitable than others for use with inverter/ | ||
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AVR equipped generators will audibly struggle and eventually stall when overloaded, signalling there is an issue. They are also better able to cope with a brief high current load which would overload an inverter based generator. | AVR equipped generators will audibly struggle and eventually stall when overloaded, signalling there is an issue. They are also better able to cope with a brief high current load which would overload an inverter based generator. | ||
- | Inverter based generators have a characteristic where the motor continues to run even if the unit has electronically overloaded and no longer delivering power. It may appear that the generator is operating and the system is charging when it isn't. These units are also more easily overloaded by surge loads. | + | Inverter based generators have a characteristic where the motor continues to run even if the unit has electronically overloaded and no longer delivering power. It may appear that the generator is operating and the system is charging when it isn't. These units are also more easily overloaded by surge loads, as they are electronically limited rather than mechanically. |
+ | |||
+ | Make sure that the generator, inverter/ | ||
+ | Eg 230V / 50hz. Do not mix and match frequencies and voltages, or parts from different regions. | ||
+ | |||
+ | |||
+ | ==== Generator Sizing ==== | ||
+ | |||
+ | It is possible to overload generators with the power demanded by the Multi' | ||
+ | |||
+ | ^ Inverter Charger Size ^ Minimum Recommended Generator Size ^ 240V AC Input Current Limit ^ | ||
+ | | 800VA | 2 kVa | 5A | | ||
+ | | 1200VA | 2.5 kVa | 7A | | ||
+ | | 1600VA | 3 kVa | 10A | | ||
+ | | 3000VA | 5 kVa | 16A | | ||
+ | | 5000VA | 8 kVa | 25A | | ||
+ | |||
+ | If your generator is smaller than the recommended size for your inverter/ | ||
+ | ==== Operation ==== | ||
It is important to note that the inverter/ | It is important to note that the inverter/ | ||
+ | |||
+ | Some generators will alter their voltage or frequency when loads change. This can be significant if the generator goes from no-load to full-load quickly. It can help to have a small ' | ||
If the generator is operating smoothly, but it still will not charge the system you may need to make some adjustments in the MultiPlus software via VEConfigure. | If the generator is operating smoothly, but it still will not charge the system you may need to make some adjustments in the MultiPlus software via VEConfigure. | ||
+ | |||
+ | |||
+ | ==== Software Changes ==== | ||
+ | |||
The settings which you should attempt first are ' | The settings which you should attempt first are ' | ||
- | If the generator will still not synchronise or disconnects, | + | If the generator will still not synchronise or disconnects, |
Lastly, adjusting the settings for Voltage and Frequency windows. These are higher risk to your appliances, they should only be used cautiously when it is confirmed that the loads will tolerate the out of specification power supply. This should be done by a competent technician with the aid of a multimeter and only opened so far as to allow for safe functionality. | Lastly, adjusting the settings for Voltage and Frequency windows. These are higher risk to your appliances, they should only be used cautiously when it is confirmed that the loads will tolerate the out of specification power supply. This should be done by a competent technician with the aid of a multimeter and only opened so far as to allow for safe functionality. | ||
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Warning: changing these settings will allow to feed-through current that may be of insufficient quality for the electrical requirements of your equipment. | Warning: changing these settings will allow to feed-through current that may be of insufficient quality for the electrical requirements of your equipment. | ||
+ | |||
+ | For information on VE-Configure and how to get started, please see this [[https:// | ||
====== 1. In the “Grid” tab of VE-Configure: | ====== 1. In the “Grid” tab of VE-Configure: | ||
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**AC low disconnect: | **AC low disconnect: | ||
- | **AC Low connect:** minimum value: at this value or any higher value, the MultiPlus will reconnect after having disconnected (default = 187Vac). | + | On generators where the output voltage drops under load, setting |
+ | The reason this happens is that the Multi will synchronise and follow the generator voltage as it sags. | ||
+ | |||
+ | If the generator is disconnected under load (either due to low-voltage disconnection, | ||
+ | |||
+ | As overload is driven by current, not power, this can result in an overload. | ||
+ | |||
+ | By increasing this minimum voltage level, you tell the inverter/ | ||
+ | |||
+ | **AC Low connect:** minimum value: at this value or any higher value, the MultiPlus will reconnect after having disconnected (default = 187Vac). | ||
===== 1.4 Maximum voltage levels ===== | ===== 1.4 Maximum voltage levels ===== | ||
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**AC high connect:** maximum value: at this value or any lower value, the MultiPlus will reconnect after having disconnected (default = 265Vac). | **AC high connect:** maximum value: at this value or any lower value, the MultiPlus will reconnect after having disconnected (default = 265Vac). | ||
+ | |||
+ | |||
+ | |||
+ | ===== 1.5 Loss of mains detection (LOM) ===== | ||
+ | |||
+ | For Full information on Loss of Mains detection, please see [[ve.bus: | ||
+ | |||
+ | |||
+ | ===== Example configuration in VEConfigure ===== | ||
+ | |||
+ | * A generator that requires LOM to be disabled. | ||
+ | * Generator on AC in 1, and grid on AC in 2, as recommended. | ||
+ | |||
+ | {{ : | ||
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{{:: | {{:: | ||
- | ===== 2.1 Load impact limitation ===== | ||
- | **Dynamic current limiter** : (default = disabled) | + | ===== 2.1 Dynamic current limiter |
+ | |||
+ | (default = disabled) | ||
This feature is intended to reduce load impacts on low-power generators, such as portable inverter technology models. These generators may be unable to respond to sudden load impacts. | This feature is intended to reduce load impacts on low-power generators, such as portable inverter technology models. These generators may be unable to respond to sudden load impacts. | ||
By activating the limiter, the **PowerAssist®** function of the MultiPlus will absorb the change in load and transfer it smoothly to the generator, giving it time to react. | By activating the limiter, the **PowerAssist®** function of the MultiPlus will absorb the change in load and transfer it smoothly to the generator, giving it time to react. | ||
+ | |||
+ | ===== 2.2 AC Input Current Limit ===== | ||
+ | |||
+ | The charger on the Multiplus is very powerful. If you have an existing generator that is not able to supply the maximum charging current of the Multi, you will need to adjust the AC Input Current Limit in the General Tab of VE-Configure. | ||
+ | |||
+ | A reasonable starting point for the AC Current input limit is 80% of the generator capacity in Watts. For example: | ||
+ | |||
+ | a 5kVA generator typically provides about 4 kW | ||
+ | |||
+ | 80% of 4 kW is 3200 W | ||
+ | |||
+ | 3200 W / 230 V volts = 13.9 A | ||
+ | |||
+ | Set the AC Current Input Limit to 13 A | ||
+ | |||
+ | If you find the generator is still overloading, | ||
+ | |||
+ | There is another additional setting in the Charger Tab for DC current limiting. | ||
+ | |||
+ | The AC input current should be adjusted first, as it also takes into account the PowerAssist functionality. | ||
+ | |||
+ | The Multi is able to synchronise the generator waveform with it's own and provide power to the loads from the generator as well charging the battery. This means it still possible to overload the generator with a low 'DC Charger current limit' if the AC input limit is not also set correctly to the size of the generators output. | ||
+ | |||
====== 3. In the " | ====== 3. In the " | ||
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Disadvantage of using this option is that the input power factor, normally equal or close to 1, will be degraded. This function should be used only when the preceding ones are ineffective. | Disadvantage of using this option is that the input power factor, normally equal or close to 1, will be degraded. This function should be used only when the preceding ones are ineffective. | ||
+ | |||
+ | This leading or lagging power factor will have the effect of demanding more kVa from the generator for the same or less DC Watts delivered to the batteries. You may need to further reduce the DC Current Limit in the Charger tab of VEConfigure if the generator continues to overload after changing this setting. | ||
+ | |||
**Important note:** | **Important note:** | ||
A detailed description of all settings is available in the VE-Configure help menu, and more instructions are available in our manuals. | A detailed description of all settings is available in the VE-Configure help menu, and more instructions are available in our manuals. | ||
+ | |||
+ | |||
+ | ====== Further Reading ====== | ||
+ | |||
+ | There have been extensive articles and documentation written about generators and their interaction with Victron systems. This includes troubleshooting, | ||
+ | |||
+ | [[https:// | ||
+ | |||
+ | [[https:// | ||
+ | |||
+ | [[https:// | ||
+ | |||
+ | [[https:// | ||
+ | |||
+ | [[https:// | ||
+ | |||
+ | |||
+ | |||
+ | |||
+ | ===== DISQUS ===== | ||
+ | ~~DISQUS~~ | ||
+ |
multiplus_faq.txt · Last modified: 2023-02-16 01:50 by guy_stewart