{"product_id":"renogy-12v-40a-dc-to-dc-battery-charger","title":"12V 40A DC to DC Battery Charger","description":"\u003cp\u003e\u003cstrong\u003e40A, 584W, supplied with the temperature sensor and ignition wire.\u003c\/strong\u003e The middle of Renogy's alternator-only range — a sensible step up when 30A is not putting enough back on a driving day and you already have solar handled separately.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e40A maximum output\u003c\/strong\u003e, 584W\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eEuro 6 smart alternators\u003c\/strong\u003e, 12–16V input; traditional 13.2–16V\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e94% charging efficiency\u003c\/strong\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTemperature sensor and ignition wire included\u003c\/strong\u003e\n\u003c\/li\u003e\n\u003cli\u003eReverse polarity, overvoltage, overcurrent and over-temperature protection\u003c\/li\u003e\n\u003cli\u003e1.88kg, 236.5 × 152.5 × 58mm\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eWhat 40A is worth on a driving day\u003c\/h3\u003e\u003cp\u003e40A is roughly 500Wh per hour of driving into a 12V bank. Two hours on the motorway is a meaningful refill for a 200Ah pack — the point at which alternator charging stops being a trickle and starts being your primary source between October and March, when the roof contributes very little.\u003c\/p\u003e\u003ch3\u003eCheck the alternator can give it\u003c\/h3\u003e\u003cp\u003eDrawing 40A at the leisure end means pulling appreciably more than that from the alternator once you account for the cab loads already on it. On a small van with a modest alternator, running this flat out alongside headlights, heater blower and heated screen is asking a lot. If in doubt, size down rather than up — or check the alternator rating before committing.\u003c\/p\u003e\u003ch3\u003eBefore you order\u003c\/h3\u003e\u003cp\u003eTerminals take 8AWG to 6AWG. Fuses are specified at 60A input and 50A output. The included temperature sensor is worth fitting rather than leaving in the box: it lets the charger back off when the battery is cold, which is exactly when you want it to.\u003c\/p\u003e","brand":"Renogy","offers":[{"title":"Default Title","offer_id":51358083023015,"sku":"RCB40D1U-BT2-UK","price":109.99,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0770\/1158\/3143\/files\/RCB40D1U-BT2-UK_378841ad-f4b5-40ca-a3df-48a34cd81c1e.jpg?v=1789800304","url":"https:\/\/shop.roamwired.com\/products\/renogy-12v-40a-dc-to-dc-battery-charger","provider":"Roam Wired Shop","version":"1.0","type":"link"}