From 82cb1ff27a6390200e683aea03bfcf114fea2112 Mon Sep 17 00:00:00 2001
From: Timo Tomasini <timo@tomasini-mail.de>
Date: Sun, 17 Aug 2025 13:46:37 +0200
Subject: [PATCH] Zaptec: add passive mode for externally managed load
 distribution systems (#23023)

---
 charger/zaptec.go                        | 14 ++++++++++++--
 templates/definition/charger/zaptec.yaml | 10 ++++++++++
 2 files changed, 22 insertions(+), 2 deletions(-)

diff --git a/charger/zaptec.go b/charger/zaptec.go
index 073593008..b73738208 100644
--- a/charger/zaptec.go
+++ b/charger/zaptec.go
@@ -48,6 +48,7 @@ type Zaptec struct {
 	version    int
 	enabled    bool
 	priority   bool
+	passive    bool
 }
 
 func init() {
@@ -62,6 +63,7 @@ func NewZaptecFromConfig(ctx context.Context, other map[string]interface{}) (api
 		User, Password string
 		Id             string
 		Priority       bool
+		Passive        bool
 		Cache          time.Duration
 	}{
 		Cache: time.Second,
@@ -75,11 +77,11 @@ func NewZaptecFromConfig(ctx context.Context, other map[string]interface{}) (api
 		return nil, api.ErrMissingCredentials
 	}
 
-	return NewZaptec(ctx, cc.User, cc.Password, cc.Id, cc.Priority, cc.Cache)
+	return NewZaptec(ctx, cc.User, cc.Password, cc.Id, cc.Priority, cc.Passive, cc.Cache)
 }
 
 // NewZaptec creates Zaptec charger
-func NewZaptec(ctx context.Context, user, password, id string, priority bool, cache time.Duration) (api.Charger, error) {
+func NewZaptec(ctx context.Context, user, password, id string, priority bool, passive bool, cache time.Duration) (api.Charger, error) {
 	log := util.NewLogger("zaptec").Redact(user, password)
 
 	if !sponsor.IsAuthorized() {
@@ -90,6 +92,7 @@ func NewZaptec(ctx context.Context, user, password, id string, priority bool, ca
 		Helper:   request.NewHelper(log),
 		log:      log,
 		priority: priority,
+		passive:  passive,
 	}
 
 	// setup cached values
@@ -235,6 +238,13 @@ func (c *Zaptec) Enable(enable bool) error {
 }
 
 func (c *Zaptec) chargerUpdate(data zaptec.Update) error {
+	if c.passive {
+		if data.MaxChargeCurrent != nil || data.MinChargeCurrent != nil || data.OfflineChargeCurrent != nil {
+			c.log.DEBUG.Println("zaptec: passive mode: skipping chargerUpdate with current fields set")
+			return nil
+		}
+	}
+
 	uri := fmt.Sprintf("%s/api/chargers/%s/update", zaptec.ApiURL, c.instance.Id)
 
 	req, _ := request.New(http.MethodPost, uri, request.MarshalJSON(data), request.JSONEncoding)
diff --git a/templates/definition/charger/zaptec.yaml b/templates/definition/charger/zaptec.yaml
index 84d062805..d536fa0d5 100644
--- a/templates/definition/charger/zaptec.yaml
+++ b/templates/definition/charger/zaptec.yaml
@@ -19,8 +19,18 @@ params:
       en: Charger ID
   - name: user
   - name: password
+  - name: passive
+    type: bool
+    description:
+      de: "Passivmodus"
+      en: "Passive mode"
+    help:
+      de: "evcc erteilt nur Ladefreigaben/Ladesperren (keine Stromregelung). Aktiviere diese Option nur, wenn die Wallbox Teil eines externen Lastmanagement Systems ist und Stromänderungen ablehnt (HTTP 403)."
+      en: "evcc only grants charging authorisations/blocks (no current control). Only activate this option if the wallbox is part of an external load management system and rejects current changes (HTTP 403)."
+    advanced: true
 render: |
   type: zaptec
   id: {{ .id }}
   user: {{ .user }}
   password: '{{ .password }}'
+  passive: {{ .passive }}