diff --git a/Bat_EV_SDL _V2/module.php b/Bat_EV_SDL _V2/module.php
index 5eba5bf..e766dae 100644
--- a/Bat_EV_SDL _V2/module.php	
+++ b/Bat_EV_SDL _V2/module.php	
@@ -2,7 +2,7 @@
 
 class Bat_EV_SDL_V2 extends IPSModule
 {
-    private const HOURS = 0.5; // 30 Minuten Fenster
+    private const HOURS = 0.5; // 30 Minuten
 
     public function Create()
     {
@@ -32,12 +32,8 @@ class Bat_EV_SDL_V2 extends IPSModule
         // Debug
         $this->RegisterVariableString("CalcJSON", "Berechnung (JSON)", "", 99);
 
-        // Cache Buffer
-        $this->RegisterBuffer("BatCacheHash", "");
-        $this->RegisterBuffer("BatCacheJSON", "[]");
-
-        // Timer
-        $this->RegisterTimer("UpdateTimer", 0, 'GEF_Update($_IPS["TARGET"]);');
+        // Timer: wichtig -> Prefix muss passen
+        $this->RegisterTimer("UpdateTimer", 0, 'Bat_EV_SDL_V2_Update($_IPS["TARGET"]);');
     }
 
     public function ApplyChanges()
@@ -47,7 +43,7 @@ class Bat_EV_SDL_V2 extends IPSModule
         $intervalMin = (int)$this->ReadPropertyInteger("UpdateInterval");
         $this->SetTimerInterval("UpdateTimer", ($intervalMin > 0) ? $intervalMin * 60 * 1000 : 0);
 
-        // Cache neu bauen wenn Properties geändert wurden
+        // Cache neu bauen (force)
         $this->BuildBatteryCache(true);
 
         $this->Update();
@@ -77,7 +73,7 @@ class Bat_EV_SDL_V2 extends IPSModule
             // Cache nur neu bauen, wenn nötig
             $this->BuildBatteryCache(false);
 
-            $cache = json_decode($this->GetBuffer("BatCacheJSON"), true);
+            $cache = json_decode($this->GetBufferSafe("BatCacheJSON"), true);
             if (!is_array($cache) || empty($cache["bats"])) {
                 $this->WriteAllZero("cache empty/invalid");
                 return;
@@ -116,23 +112,21 @@ class Bat_EV_SDL_V2 extends IPSModule
                 $real_kWh = $capKWh / 100.0 * $socPct;
 
                 // vorkalkuliert:
-                $typ       = (string)($c["typ"] ?? ("Bat " . ($i + 1)));
-                $underKWh  = (float)($c["underKWh"] ?? 0.0);
-                $upKWh     = (float)($c["upKWh"] ?? 0.0);
-                $SDL_kWh   = (float)($c["SDL_kWh_total"] ?? 0.0);
-                $EV_kWh    = (float)($c["EV_kWh_total"] ?? 0.0);
+                $typ        = (string)($c["typ"] ?? ("Bat " . ($i + 1)));
+                $underKWh   = (float)($c["underKWh"] ?? 0.0);
+                $upKWh      = (float)($c["upKWh"] ?? 0.0);
+                $SDL_kWh    = (float)($c["SDL_kWh_total"] ?? 0.0);
+                $EV_kWh     = (float)($c["EV_kWh_total"] ?? 0.0);
 
                 $sdlShareKW = (float)($c["sdlShareKW"] ?? 0.0);
                 $evShareKW  = (float)($c["evShareKW"] ?? 0.0);
 
-                // Defaults pro Batterie
+                // Defaults
                 $EV_SOC = 0.0;
                 $SDL_SOC = 0.0;
 
-                $sdlDisKW = 0.0;
-                $evDisKW  = 0.0;
-                $sdlChKW  = 0.0;
-                $evChKW   = 0.0;
+                $sdlDisKW = 0.0; $evDisKW = 0.0;
+                $sdlChKW  = 0.0; $evChKW  = 0.0;
 
                 $real_kWh_ev  = 0.0;
                 $real_kWh_sdl = 0.0;
@@ -182,19 +176,17 @@ class Bat_EV_SDL_V2 extends IPSModule
                     $real_kWh_sdl = $real_kWh;
                 }
 
-                // Null/Full Abdeckung (wie vorher)
+                // Null/Full
                 if ($real_kWh <= 0.0) {
                     $sdlDisKW = 0.0;
                     $real_kWh_ev = 0.0;
                     $real_kWh_sdl = 0.0;
                 } elseif ($real_kWh >= $capKWh) {
                     $sdlChKW = 0.0;
-
                     $real_kWh_ev  = $capKWh - 2.0 * $underKWh;
                     $real_kWh_sdl = 2.0 * $underKWh;
                 }
 
-                // Negative verhindern
                 $real_kWh_ev  = max(0.0, $real_kWh_ev);
                 $real_kWh_sdl = max(0.0, $real_kWh_sdl);
 
@@ -212,7 +204,6 @@ class Bat_EV_SDL_V2 extends IPSModule
                 $SDL_kWh_ges += $SDL_kWh;
                 $EV_kWh_ges  += $EV_kWh;
 
-                // Debug pro Batterie
                 $calc["batteries"][] = [
                     "idx" => $c["idx"] ?? $i,
                     "typ" => $typ,
@@ -239,11 +230,9 @@ class Bat_EV_SDL_V2 extends IPSModule
                 ];
             }
 
-            // Prozent gesamt
             $evPosPct  = ($EV_kWh_ges  > 0.0) ? ($real_kWh_ev_ges  / $EV_kWh_ges  * 100.0) : 0.0;
             $sdlPosPct = ($SDL_kWh_ges > 0.0) ? ($real_kWh_sdl_ges / $SDL_kWh_ges * 100.0) : 0.0;
 
-            // Werte setzen
             $this->SetIdentValue("SDL_Pos", round($sdlPosPct, 3));
             $this->SetIdentValue("SoC_EV",  round($evPosPct, 3));
 
@@ -275,10 +264,6 @@ class Bat_EV_SDL_V2 extends IPSModule
         }
     }
 
-    /**
-     * Baut Cache nur neu, wenn sich Inputs geändert haben.
-     * Cache enthält alles, was NICHT vom SoC abhängt.
-     */
     private function BuildBatteryCache(bool $force): void
     {
         $batteriesRaw = $this->ReadPropertyString("Batteries");
@@ -291,24 +276,20 @@ class Bat_EV_SDL_V2 extends IPSModule
             "hours"     => $hours
         ]));
 
-        $oldHash = $this->GetBuffer("BatCacheHash");
+        $oldHash = $this->GetBufferSafe("BatCacheHash");
         if (!$force && $oldHash === $hash) {
-            return; // nix zu tun
+            return;
         }
 
         $batteries = json_decode($batteriesRaw, true);
-        if (!is_array($batteries)) {
-            $batteries = [];
-        }
+        if (!is_array($batteries)) $batteries = [];
 
-        // Summe Batterie-Maxleistungen
         $sumBatPowerW = 0.0;
         foreach ($batteries as $b) {
             $p = (float)($b["powerbat"] ?? 0);
             if ($p > 0) $sumBatPowerW += $p;
         }
 
-        // Cache Grundstruktur
         $cache = [
             "inputs" => [
                 "SDL_Leistung_W" => $sdlTotalW,
@@ -334,18 +315,14 @@ class Bat_EV_SDL_V2 extends IPSModule
             $pBatkW = $pBatW / 1000.0;
 
             $capKWh = max(0.0, (float)($b["capazity"] ?? 0));
-            if ($capKWh <= 0.0) {
-                continue;
-            }
+            if ($capKWh <= 0.0) continue;
 
             $socVarId = (int)($b["soc"] ?? 0);
             $typ      = (string)($b["typ"] ?? ("Bat " . ($idx + 1)));
 
-            // Anteil SDL/EV über Leistungsanteil (wie vorher)
             $sdlShareKW = ($sumBatPowerkW > 0.0) ? ($sdlTotalkW / $sumBatPowerkW * $pBatkW) : 0.0;
             $evShareKW  = $pBatkW - $sdlShareKW;
 
-            // untere Grenze
             $underKWh = $sdlShareKW * $hours;
             $underKWh = max(0.0, min($underKWh, $capKWh / 2.0));
 
@@ -378,7 +355,11 @@ class Bat_EV_SDL_V2 extends IPSModule
         $this->SendDebug("Cache", "Battery cache rebuilt (" . count($cache["bats"]) . " bats)", 0);
     }
 
-    // ---------------- Helpers ----------------
+    private function GetBufferSafe(string $name): string
+    {
+        $v = $this->GetBuffer($name);
+        return is_string($v) ? $v : "";
+    }
 
     private function WriteAllZero(string $reason): void
     {