reading the user manual of this unit implies that I don't need to power through the mppt that comes with the solar panels. Just connect straight to d250s Does anybody have info otherwise?
You are correct - use only one charge controller as shown on the picture. The D250s common earth is the battery negative/earth connection (as per the pic).
-- Edited by Wanderlust on Monday 20th of February 2017 03:58:22 PM
Be aware of the one major flaw of the Ctek designs is that they do not take into account different chemistries.
Ctek will not release the details of what are the terminal voltages that their chargers change rates.
Industry testing has shown that ctek units charge all batteries at the same voltage steps that would be used for a flooded battery, which is not ideal for proper charging of Gell, AGM and calcium, which require different points to change from bulk to absorption to float, and they are not suitable for lithium at all.
With all DC to DC chargers you must bypass your panel's MPPT controller. MPPT controllers must have a connection direct to the battery, the panel's controller wont turn on if you hook up the controller to a controller.
Thank you hy life for that info. Do you think it will be a better option then that given the c tek charging ability , that I should leave the mppt charger on the panels and bypass the d250 s. ? Ps I have an AGM house battery.
I have never had a charge controller on any solar panel I own. In the camper trailer, the FLA Deep Cycle was hard wired to the panel. In the van, panel to a 250S, to an AGM, set and forget. In the campervan, I have alternator and panels hard wired to the 250S and then straight to a variety of technologies, including a DIY LiFePo battery, one at a time. I disconnect the charger when the cell voltage on the Lithium gets to 3.55 Volts.
Iza
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Iza
Semi-permanent state of being Recreationally Outraged as a defence against boredom during lockdown.
I have never had a charge controller on any solar panel I own. In the camper trailer, the FLA Deep Cycle was hard wired to the panel. In the van, panel to a 250S, to an AGM, set and forget. In the campervan, I have alternator and panels hard wired to the 250S and then straight to a variety of technologies, including a DIY LiFePo battery, one at a time. I disconnect the charger when the cell voltage on the Lithium gets to 3.55 Volts.
Iza
HI izabarack
I would say you are incorrect in saying that you do not have a charge controller. The charge controller is YOU and is a manual control system. Also you do not say what size the panels are or the batteries.
Is the 250S a controller ? Hard wired, permanent or switchable on and off ?
Just in case others may think that they may be able to get away with out something important
Jaahn
-- Edited by Jaahn on Saturday 25th of February 2017 06:10:15 PM
-- Edited by Jaahn on Saturday 25th of February 2017 06:10:36 PM
I would say you are incorrect in saying that you do not have a charge controller.
In the context of the original post, I am correct. For several years, I hard wired a solar panel to a FLA deep cycle battery running a fridge, without issue.
Your reply does nothing to help answer the original question.
Iza
__________________
Iza
Semi-permanent state of being Recreationally Outraged as a defence against boredom during lockdown.
