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electrical:12v:alternator [2019/10/01 12:33]
frater_secessus [limitations] |
electrical:12v:alternator [2020/01/21 21:22]
frater_secessus [isolators] |
| * when batteries are deeply discharged | * when batteries are deeply discharged |
| * when [[electrical:12v:alt and solar|combined with solar]] or some other higher-voltage charging source | * when [[electrical:12v:alt and solar|combined with solar]] or some other higher-voltage charging source |
| * when used with battery chemistries like [[electrical:12v:lifepo4_batteries_thread|lithium]] that do not need [[electrical:12v:charging|staged charging]]. | * when used with battery chemistries like [[electrical:12v:deep_cycle_battery#lithium_chemistries|lithium]] that do not need [[electrical:12v:charging|staged charging]]. |
| * when used with a [[electrical:12v:b2b|battery-to-battery boosting charger]] that can produce correct charging voltage | * when used with a [[electrical:12v:b2b|battery-to-battery boosting charger]] that can produce correct charging voltage |
| |
| ===== limitations ===== | ===== limitations ===== |
| |
| Alternator charging is generally only practical for the [[electrical:12v:charging|bulk charge stage]] due to relatively low voltage output and the [[electrical:12v:charging|long time periods required for absorption]]. It is unlikely to get the house battery completely charged unless one is driving significant distances. This can have an impact on [[electrical:batterycide|battery longevity]]. If one drives often [[electrical:12v:alt_and_solar|a combination of the alternator doing bulk charging and a small solar doing the rest]] is good match. | Alternator charging is generally only practical for the [[electrical:12v:charging|bulk charge stage]] due to relatively low voltage output and the [[electrical:12v:charging|long time periods required for absorption]].(([[electrical:12v:b2b|DC-DC chargers]] can help with the voltage)) It is unlikely to get the house battery completely charged unless one is driving significant distances. This can have an impact on [[electrical:batterycide|battery longevity]]. If one drives often [[electrical:12v:alt_and_solar|a combination of the alternator doing bulk charging and a small solar doing the rest]] is good match. |
| |
| See [[electrical:12v:mandatory solar|Is Solar Mandatory?]] for ideas on how to charge primarly by alternator. | See [[electrical:12v:mandatory solar|Is Solar Mandatory?]] for ideas on how to charge primarly by alternator. |
| - [[http://amzn.to/2gVmLFU|{{ https://images-na.ssl-images-amazon.com/images/I/418qcncjT0L._AC_US218_.jpg|}}]]voltage sensing relays - this kind of isolator is **installed between the house and starter batteries**. It does not get trigger voltage from the fuse panel but rather reads the voltages of one or both batteries to know when to switch on. \\ This kind of isolator may have a "combine" override function to enable self-jumpstarting. | - [[http://amzn.to/2gVmLFU|{{ https://images-na.ssl-images-amazon.com/images/I/418qcncjT0L._AC_US218_.jpg|}}]]voltage sensing relays - this kind of isolator is **installed between the house and starter batteries**. It does not get trigger voltage from the fuse panel but rather reads the voltages of one or both batteries to know when to switch on. \\ This kind of isolator may have a "combine" override function to enable self-jumpstarting. |
| - [[http://amzn.to/2h2tDxp|single voltage sensing]] - this type reads the voltage of only one battery. In the case of an RV it would read the voltage of the starting battery. When it is high enough (ie, charged or being charged by alternator) it connects the starting and house batteries. Example: [[http://amzn.to/2h2tDxp|Sure Power 1314]]. [secessus says: "IMO the practical benefit (if any) to charging the starter battery "first" is keeping the load on the alternator reasonable."] | - [[http://amzn.to/2h2tDxp|single voltage sensing]] - this type reads the voltage of only one battery. In the case of an RV it would read the voltage of the starting battery. When it is high enough (ie, charged or being charged by alternator) it connects the starting and house batteries. Example: [[http://amzn.to/2h2tDxp|Sure Power 1314]]. [secessus says: "IMO the practical benefit (if any) to charging the starter battery "first" is keeping the load on the alternator reasonable."] |
| - [[http://amzn.to/2gVmLFU|dual voltage sensing]] - this type reads the voltage from both batteries and when either is high enough it connects the batteries. This may or may not be what an RVer wants, as it could consume some solar power to to engergize the solenoid and charge the starter battery. It would also backfeed excessive [[electrical:12v:charging|equalization]] voltages to the coach system. Example: [[http://amzn.to/2gVmLFU|Sure Power 1315]] | - [[http://amzn.to/2gVmLFU|dual voltage sensing]] - this type reads the voltage from both batteries and when either is high enough it connects the batteries. This may or may not be what an RVer wants, as it could consume some solar power to to engergize the solenoid and charge the starter battery. It would also backfeed excessive [[electrical:12v:charging|equalization]] voltages to the coach system. Battery chemistries with higher resting voltages like LiFePO4((or 4S non-LFP lipo)) could also trigger the isolator. Examples: [[http://amzn.to/2gVmLFU|Sure Power 1315]], [[https://amzn.to/37gcdIv|BlueSea SI-ACR]] |
| - DC-DC isolators (aka //[[electrical:12v:b2b|b2b]] isolators//) that boost charging voltage to [[electrical:12v:charging|Absorption]] voltages | - DC-DC isolators (aka //[[electrical:12v:b2b|b2b]] isolators//) that boost charging voltage to [[electrical:12v:charging|Absorption]] voltages |
| - [[http://amzn.to/2gVwmKw|solid state isolator]] - an electronic device which uses diodes to prevent depletion of the starter battery. **Isolators are generally brick-shaped**. Diode-based isolators have a **0.5v - 1v drop** between the alternator and house battery. This may be desirable if the house battery is a lower-voltage chemistry like [[electrical:12v:lifepo4_batteries_thread|LiFePO4]]. Some solid state isolaters use FETs and diodes in tandem to reduce voltage drop. \\ Note: solid state relays can't combine batteries for self-jumpstarting. | - [[http://amzn.to/2gVwmKw|solid state isolator]] - an electronic device which uses diodes to prevent depletion of the starter battery. **Isolators are generally brick-shaped**. Diode-based isolators have a **0.5v - 1v drop** between the alternator and house battery. This may be desirable if the house battery is a lower-voltage chemistry like [[electrical:12v:lifepo4_batteries_thread|LiFePO4]]. Some solid state isolaters use FETs and diodes in tandem to reduce voltage drop. \\ Note: solid state relays can't combine batteries for self-jumpstarting. |
