From de5b93e29d19abc2e5d9746dcb66d7eb4e42b117 Mon Sep 17 00:00:00 2001
From: mfuchs1984 <57141790+mfuchs1984@users.noreply.github.com>
Date: Mon, 30 Mar 2026 11:12:46 +0200
Subject: [PATCH] Bender: handle invalid power meter reading (#28644)

---
 charger/bender.go | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/charger/bender.go b/charger/bender.go
index a48a58792..68029ceda 100644
--- a/charger/bender.go
+++ b/charger/bender.go
@@ -372,7 +372,16 @@ func (wb *BenderCC) currentPower() (float64, error) {
 		return 0, err
 	}
 
-	return float64(binary.BigEndian.Uint32(b)), nil
+	u := binary.BigEndian.Uint32(b)
+
+	// some Bender chargers temporarily return 0xffffffff
+	// return error in this case to trigger retry and avoid wrong power readings
+	// https://github.com/evcc-io/evcc/discussions/27736
+	if u == math.MaxUint32 {
+		return 0, api.ErrMustRetry
+	}
+
+	return float64(u), nil
 }
 
 // removed: https://github.com/evcc-io/evcc/issues/13726