User Tools

Site Tools


electrical:12v:b2b

Differences

This shows you the differences between two versions of the page.

Link to this comparison view

Both sides previous revision Previous revision
Next revision
Previous revision
Next revision Both sides next revision
electrical:12v:b2b [2018/12/28 10:38]
frater_secessus [Sterling]
electrical:12v:b2b [2019/06/02 13:58]
frater_secessus [Battery to battery chargers]
Line 1: Line 1:
 ====== Battery to battery chargers ====== ====== Battery to battery chargers ======
  
-A b2b (or //dc-dc//) charger is a type of [[electrical:​12v:​alternator|isolator]] that boosts charging voltage to the house battery. ​ These typically cost more and deliver ​less current than normal isolator types+A b2b (or //dc-dc//) charger is a type of [[electrical:​12v:​alternator|isolator]] that boosts charging voltage to the house battery. ​ These typically cost more and are rated for less current than normal isolator types.((but they will provide more current overall during longish drives. ​ See below.))
  
 [[https://​amzn.to/​2RY2GNQ|{{ https://​images-na.ssl-images-amazon.com/​images/​I/​3131jBgz9LL._AC_US218_.jpg}}]] [[https://​amzn.to/​2RY2GNQ|{{ https://​images-na.ssl-images-amazon.com/​images/​I/​3131jBgz9LL._AC_US218_.jpg}}]]
-This kind of controller boosts the chassis voltage to voltage appropriate for proper Absorption.  ​+This kind of controller boosts the chassis voltage to voltage appropriate for proper ​lead-acid ​Absorption.  ​
  
 +
 +===== limitations =====
 +
 +Lead-acid batteries require two things to get fully charged:
 +  - a high enough [[electrical:​12v:​charging#​absorption_stage|Absorption voltage]] (Vabs)
 +  - enough //time// at that voltage for the battery to stop accepting much current.(([[electrical:​12v:​battery_capacity|C/​100]] to C/200))
 +
 +DC-DC chargers address the first requirement,​ but unless you are driving for //hours// the isolator won't have enough time to fully charge the batteries. ​ DC-DC charging is very effective on cruisers (boats) that run the engines for hours each day.  They will, however, put more current into the bank due to their higher voltage.
 ===== CTEK D250 series ===== ===== CTEK D250 series =====
  
Line 12: Line 20:
 The [[https://​amzn.to/​2TozjWu|SmartPass accessory]] bypasses the D250SA when the house battery wants > 20A of current. ​ This will generally happen in the first half of Bulk mode. When the house battery demand drops below 20A control is handed back to the D250SA for boosting to Absorption voltage.((https://​www.4x4community.co.za/​forum/​showthread.php/​292297-Ctek-250-upgrade-to-smartpass?​p=3823781#​post3823781))\\ The [[https://​amzn.to/​2TozjWu|SmartPass accessory]] bypasses the D250SA when the house battery wants > 20A of current. ​ This will generally happen in the first half of Bulk mode. When the house battery demand drops below 20A control is handed back to the D250SA for boosting to Absorption voltage.((https://​www.4x4community.co.za/​forum/​showthread.php/​292297-Ctek-250-upgrade-to-smartpass?​p=3823781#​post3823781))\\
  
-Note:  the CTEK D250SA((and the pre-2018 D250**S** model)) panel voltage (Vpanel) maximum is 23v.((https://​www.ctek.com/​storage/​ma/​b21ecd5d5e5943a995474cf36d586451/​956c3913c8cc4319bb4e47baea0c6d82/​pdf/​A78BBB08A9DF8976DB79E21271E091489ACEF47A/​D250SA-manual-UK-EN.pdf,​ pdf)) +Note:  the CTEK D250SA((and the pre-2018 D250**S** model)) panel voltage (Vpanel) maximum is 23v.((https://​www.ctek.com/​storage/​ma/​b21ecd5d5e5943a995474cf36d586451/​956c3913c8cc4319bb4e47baea0c6d82/​pdf/​A78BBB08A9DF8976DB79E21271E091489ACEF47A/​D250SA-manual-UK-EN.pdf,​ pdf))  It requires >= 80w of solar for reliable solar charging.(())(()) ​ There are reports that the MPPT algorithm is not particularly robust and is better thought of as an add-on for the alternator charging circuit.((https://​expeditionportal.com/​forum/​threads/​ctek-250s-poor-solar-performance.198052/​)) ​ FIXME 
 + 
 ===== Sterling ===== ===== Sterling =====
  
Line 22: Line 30:
 [[https://​amzn.to/​2VgTre7|{{ https://​images-na.ssl-images-amazon.com/​images/​I/​417F858GCdL._AC_US218_.jpg}}]] [[https://​amzn.to/​2VgTre7|{{ https://​images-na.ssl-images-amazon.com/​images/​I/​417F858GCdL._AC_US218_.jpg}}]]
 Redarc makes [[https://​amzn.to/​2VgTre7|a 25A b2b charge with MPPT]] similar to the CTEK. Redarc makes [[https://​amzn.to/​2VgTre7|a 25A b2b charge with MPPT]] similar to the CTEK.
 +
 +===== Ring Automotive =====
 +
 +Ring makes [[https://​www.ringautomotive.com/​en/​product/​RSCDC30|a 30A DC-DC charger]].
electrical/12v/b2b.txt · Last modified: 2019/11/12 09:48 by frater_secessus