Both sides previous revision
Previous revision
Next revision
|
Previous revision
Next revision
Both sides next revision
|
electrical:12v:alternator [2020/06/23 11:58] frater_secessus [isolators] |
electrical:12v:alternator [2020/06/25 11:48] frater_secessus [manual switch] |
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. | 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. | Vehicles with //smart// (variable voltage) alternators may not be suitable for charging with normal isolators.((https://www.redarc.com.au/how-do-i-know-if-i-have-a-variable-voltage-smart-alternator)) See [[electrical:12v:b2b|DC-DC chargers]]. |
| |
| See [[electrical:12v:mandatory solar|Is Solar Mandatory?]] for ideas on how to charge primarily by alternator. |
| |
| |
| |
| |
==== manual switch ==== | |
| |
[[https://amzn.to/2VaL8SG|{{https://m.media-amazon.com/images/I/81n-ap+0lPL._AC_UY218_.jpg }}]]The simplest and least-featured isolator is a //manual switch//. | |
| |
Pro: very little to go wrong. | |
| |
Con: must be operated manually and one must remember to do so. Leaving the switch in the combined position when not driving will drain both the house and starter battery. | |
| |
| |
- DC-DC isolators (aka //[[electrical:12v:b2b|b2b]] isolators//) that boost alternator voltage to [[electrical:12v:charging|more appropriate levels for lead chemistries]] and can do multistage charging. These have [[electrical:12v:b2b|their own page]]. | - DC-DC isolators (aka //[[electrical:12v:b2b|b2b]] isolators//) that boost alternator voltage to [[electrical:12v:charging|more appropriate levels for lead chemistries]] and can do multistage charging. These have [[electrical:12v:b2b|their own page]]. |
| |
==== diode-based isolator ==== | ==== solid state isolator: diode-based ==== |
| |
Note: this type of isolator is no longer common for our uses. | Note: this type of isolator is no longer common for our uses. |
| |
[[http://amzn.to/2gVwmKw|Solid state isolators]] are electronic devices which use 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 wants lower-voltage charging 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|These isolators]] are electronic devices which use 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 wants lower-voltage charging 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. |
| |
| ==== solid state isolator: FET-based ==== |
| |
| This type of isolator is similar to the diode-based one above, except that FET components are used instead of diodes, preventing voltage drop. |
| |
| Example: [[https://amzn.to/2Cwjkln|Victron Argo 200A FET Battery Isolator]] |
==== manual switch ==== | ==== manual switch ==== |
| |
| [[https://amzn.to/2VaL8SG|{{https://m.media-amazon.com/images/I/81n-ap+0lPL._AC_UY218_.jpg?125 }}]]The simplest and least-featured isolator is a //manual switch//. |
| |
A [[http://amzn.to/2gsDtNc|manual battery switch]] normally has 4 positions: A, B, A+B, and Off. A would be for the starter battery and used during starting. B would be used for house use when one is not driving. A+B could be used to combine both sets for starting or for charging while driving. This kind of setup is prone to user error. A manual switch has no current or voltage losses. | A [[http://amzn.to/2gsDtNc|manual battery switch]] normally has 4 positions: A, B, A+B, and Off. A would be for the starter battery and used during starting. B would be used for house use when one is not driving. A+B could be used to combine both sets for starting or for charging while driving. This kind of setup is prone to user error. A manual switch has no current or voltage losses. |
| |
| ==== misc ==== |
| |
| [note from secessus: "not sure what's inside these solid state isolators"] |
| |
| [[https://amzn.to/3fVuKh0|{{ https://m.media-amazon.com/images/I/51XoShK5uIL._AC_UY218_.jpg?125}}]] |
| The [[electrical:12v:https://amzn.to/3fVuKh0|Magnum Energy ME-SBC]] is notable for some unusual features: |
| * configurable connect/disconnect setpoints |
| * ability to drive a solenoid, which allows for much greater current |
| |
| Xantrex makes [[https://amzn.to/3eKhkEc|a 15A Digital-Echo Charge isolator]]. |
| |
| |
| |
| |
| |
| |
===== sizing an isolator ===== | ===== sizing an isolator ===== |