multiplus_faq
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- | ====== MultiPlus FAQ ====== | + | ====== MultiPlus |
- | What to do when a MultiPlus does not accept generator power | + | __What |
- | ---- | + | __ |
- | Even when a MultiPlus operates perfectly on shore (or mains) | + | 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 |
- | This is generally caused by inferior quality of the generator power: when generator power quality is insufficient, | + | ==== Selecting a Generator ==== |
- | In fact, this current will go through the MultiPlus only if it meets minimal quality requirements; | ||
- | The sensitivity of a MultiPlus to power quality can be easily modified | + | Some generators are more suitable than others for use with inverter/ |
- | Warning: changing these settings will allow to feed-through current of insufficient quality | + | For example; some things |
- | The main parameters | + | 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, 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/ | ||
+ | |||
+ | 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. | ||
+ | |||
+ | |||
+ | ==== Software Changes | ||
+ | |||
+ | |||
+ | The settings which you should attempt first are ' | ||
+ | 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. | ||
+ | |||
+ | Electrical current will go through the MultiPlus only if it meets the programmed minimal quality requirements; | ||
+ | |||
+ | |||
+ | 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: | ||
+ | |||
+ | | ||
+ | |||
+ | ===== 1.1 Wave shape quality ===== | ||
+ | |||
+ | **UPS Function:** (default = enabled) | ||
+ | |||
+ | When the sine wave is of good quality, the Inverter of the MultiPlus will hook up on it, thus allowing a synchronised and fast transfer when the generator stops. | ||
+ | |||
+ | Many generators have more or less ill-shaped sine waves, in particular during sudden load changes. In these situations, the MultiPlus will disconnect frequently or not connect at all. The UPS function must then be deactivated. The drawback is a slightly longer transfer time. | ||
- | ===== 1.1 Frequency stability ===== | + | ===== 1.2 Frequency stability ===== |
**Accept wide input frequency range (45-65Hz): | **Accept wide input frequency range (45-65Hz): | ||
If the generator is extremely stable and if that same stability is required on the output of the MultiPlus, this setting may be disabled. | If the generator is extremely stable and if that same stability is required on the output of the MultiPlus, this setting may be disabled. | ||
- | ===== 1.2 Minimum voltage levels ===== | + | ===== 1.3 Minimum voltage levels ===== |
**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 |
- | ===== 1.3 Maximum voltage levels ===== | + | 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 ===== | ||
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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). | ||
- | ===== 1.4 Wave shape quality ===== | ||
- | **UPS Function:** (default = enabled) | ||
- | When the sine wave is of good quality, the Inverter of the MultiPlus will hook up on it, thus allowing a synchronised and fast transfer when the generator stops. | + | ===== 1.5 Loss of mains detection (LOM) ===== |
- | Many generators have more or less ill-shaped sine waves, in particular during sudden load changes. In these situations, the MultiPlus will disconnect frequently or not connect at all. The UPS function must then be deactivated. The drawback is a slightly longer transfer time. | + | For Full information on Loss of Mains detection, please see [[ve.bus: |
- | ===== 1.5 Load impact limitation | + | ===== Example configuration in VEConfigure |
- | **Dynamic current limiter** : (default = disabled) | + | |
+ | | ||
+ | |||
+ | {{ : | ||
+ | |||
+ | |||
+ | |||
+ | |||
+ | ====== 2. In the “General” tab of VE-Configure: | ||
+ | |||
+ | {{:: | ||
+ | |||
+ | |||
+ | ===== 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. | ||
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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. In the " | + | ===== 2.2 AC Input Current Limit ===== |
- | **Derating of the power factor** | + | 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 " | ||
+ | |||
+ | {{: | ||
+ | |||
+ | ===== 3.1 Derating of the power factor | ||
Some generators have a waveform which makes it difficult to charge with the normal charge mechanism. Through activating the " | Some generators have a waveform which makes it difficult to charge with the normal charge mechanism. Through activating the " | ||
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:** | ||
Line 68: | Line 170: | ||
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. | ||
+ | ====== 4. In the “Inverter” tab of VE-Configure: | ||
+ | |||
+ | ===== 4.1 PowerAssist ===== | ||
+ | |||
+ | The [[https:// | ||
+ | |||
+ | If you have a small generator and have trouble getting connected or staying connected, Disable PowerAssist to allow the device to reduce the AC input current limit. | ||
+ | |||
+ | |||
+ | |||
+ | ====== Still not connecting? ====== | ||
+ | |||
+ | If the unit is still not connecting, switch the Multi over to Charger only mode. | ||
+ | |||
+ | Try with a different generator. | ||
+ | |||
+ | There can be issues with generators with Residual Current Devices (RCD' | ||
+ | |||
+ | |||
+ | If there is still no connection, contact your dealer or distributor. Tell them the steps that you have taken already to attempt to get it to work and they can help from there. | ||
+ | |||
+ | |||
+ | ====== 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:// | ||
+ | |||
+ | [[https:// | ||
+ | |||
+ | |||
+ | |||
+ | |||
+ | ===== DISQUS ===== | ||
+ | ~~DISQUS~~ |
multiplus_faq.txt · Last modified: 2023-02-16 01:50 by guy_stewart