diff --git a/charger/daheimladen-mb.go b/charger/daheimladen-mb.go
index cf5773ce9..be25a4782 100644
--- a/charger/daheimladen-mb.go
+++ b/charger/daheimladen-mb.go
@@ -103,7 +103,9 @@ func NewDaheimLadenMB(uri string, id uint8) (api.Charger, error) {
 	if err != nil {
 		return nil, fmt.Errorf("failsafe timeout: %w", err)
 	}
-	go wb.heartbeat(time.Duration(binary.BigEndian.Uint16(b)/2) * time.Second)
+	if u := binary.BigEndian.Uint16(b); u > 0 {
+		go wb.heartbeat(time.Duration(u/2) * time.Second)
+	}
 
 	return wb, err
 }
diff --git a/charger/obo.go b/charger/obo.go
new file mode 100644
index 000000000..f96da84d0
--- /dev/null
+++ b/charger/obo.go
@@ -0,0 +1,136 @@
+package charger
+
+import (
+	"encoding/binary"
+	"fmt"
+	"time"
+
+	"github.com/evcc-io/evcc/api"
+	"github.com/evcc-io/evcc/util"
+	"github.com/evcc-io/evcc/util/modbus"
+)
+
+// Obo charger implementation
+type Obo struct {
+	log  *util.Logger
+	conn *modbus.Connection
+}
+
+const (
+	oboRegEnable     = 5
+	oboRegAmpsConfig = 6
+	oboRegStatus     = 11
+	oboRegTimeout    = 28
+)
+
+func init() {
+	registry.Add("obo", NewOboFromConfig)
+}
+
+// NewOboFromConfig creates a OBO Bettermann charger from generic config
+func NewOboFromConfig(other map[string]interface{}) (api.Charger, error) {
+	cc := modbus.Settings{
+		Baudrate: 19200,
+		Comset:   "8E1",
+		ID:       101,
+	}
+
+	if err := util.DecodeOther(other, &cc); err != nil {
+		return nil, err
+	}
+
+	return NewObo(cc.URI, cc.Device, cc.Comset, cc.Baudrate, modbus.ProtocolFromRTU(cc.RTU), cc.ID)
+}
+
+// NewObo creates OBO Bettermann charger
+func NewObo(uri, device, comset string, baudrate int, proto modbus.Protocol, slaveID uint8) (api.Charger, error) {
+	conn, err := modbus.NewConnection(uri, device, comset, baudrate, proto, slaveID)
+	if err != nil {
+		return nil, err
+	}
+
+	log := util.NewLogger("obo")
+	conn.Logger(log.TRACE)
+
+	wb := &Obo{
+		log:  log,
+		conn: conn,
+	}
+
+	// get failsafe timeout from charger
+	b, err := conn.ReadHoldingRegisters(oboRegTimeout, 1)
+	if err != nil {
+		return nil, fmt.Errorf("failsafe timeout: %w", err)
+	}
+	if u := binary.BigEndian.Uint16(b); u > 0 {
+		go wb.heartbeat(time.Duration(u/2) * time.Millisecond)
+	}
+
+	// lightshow
+	// go func() {
+	// 	conn.WriteSingleRegister(3, 1)
+	// 	for {
+	// 		for i := 0; i < 3; i++ {
+	// 			u := rand.Int31n(256)
+	// 			conn.WriteSingleRegister(uint16(i), uint16(u))
+	// 		}
+	// 		time.Sleep(10 * time.Millisecond)
+	// 	}
+	// }()
+	// time.Sleep(10 * time.Second)
+
+	return wb, nil
+}
+
+func (wb *Obo) heartbeat(timeout time.Duration) {
+	for range time.Tick(timeout) {
+		if _, err := wb.conn.ReadHoldingRegisters(dlRegSafeCurrent, 1); err != nil {
+			wb.log.ERROR.Println("heartbeat:", err)
+		}
+	}
+}
+
+// Status implements the api.Charger interface
+func (wb *Obo) Status() (api.ChargeStatus, error) {
+	b, err := wb.conn.ReadHoldingRegisters(oboRegStatus, 1)
+	if err != nil {
+		return api.StatusNone, err
+	}
+
+	switch u := binary.BigEndian.Uint16(b); u {
+	case 0, 1, 2:
+		// A..C
+		return api.ChargeStatus(string('A' + rune(u))), nil
+	default:
+		// D, F
+		return api.StatusNone, fmt.Errorf("invalid status: %d", u)
+	}
+}
+
+// Enabled implements the api.Charger interface
+func (wb *Obo) Enabled() (bool, error) {
+	b, err := wb.conn.ReadHoldingRegisters(oboRegEnable, 1)
+	if err != nil {
+		return false, err
+	}
+
+	return binary.BigEndian.Uint16(b) > 0, nil
+}
+
+// Enable implements the api.Charger interface
+func (wb *Obo) Enable(enable bool) error {
+	var u uint16
+	if enable {
+		u = 1
+	}
+
+	_, err := wb.conn.WriteSingleRegister(oboRegEnable, u)
+
+	return err
+}
+
+// MaxCurrent implements the api.Charger interface
+func (wb *Obo) MaxCurrent(current int64) error {
+	_, err := wb.conn.WriteSingleRegister(oboRegAmpsConfig, uint16(current))
+	return err
+}
diff --git a/charger/webasto-next.go b/charger/webasto-next.go
index 03c5f149b..ef1076bd2 100644
--- a/charger/webasto-next.go
+++ b/charger/webasto-next.go
@@ -97,8 +97,9 @@ func NewWebastoNext(uri string, id uint8) (api.Charger, error) {
 	if err != nil {
 		return nil, fmt.Errorf("failsafe timeout: %w", err)
 	}
-
-	go wb.heartbeat(time.Duration(binary.BigEndian.Uint16(b)/2) * time.Second)
+	if u := binary.BigEndian.Uint16(b); u > 0 {
+		go wb.heartbeat(time.Duration(u/2) * time.Second)
+	}
 
 	return wb, err
 }
diff --git a/templates/definition/charger/obo.yaml b/templates/definition/charger/obo.yaml
new file mode 100644
index 000000000..ebbda7912
--- /dev/null
+++ b/templates/definition/charger/obo.yaml
@@ -0,0 +1,14 @@
+template: obo
+products:
+  - brand: OBO Bettermann
+    description:
+      generic: Ion
+params:
+  - name: modbus
+    choice: ["rs485"]
+    baudrate: 19200
+    comset: 8E1
+    id: 101
+render: |
+  type: obo
+  {{- include "modbus" . }}
diff --git a/templates/docs/charger/obo_0.yaml b/templates/docs/charger/obo_0.yaml
new file mode 100644
index 000000000..f7ac33186
--- /dev/null
+++ b/templates/docs/charger/obo_0.yaml
@@ -0,0 +1,20 @@
+product:
+  brand: OBO Bettermann
+  description: Ion
+render:
+  - default: |
+      type: template
+      template: obo
+
+      # RS485 via adapter (Modbus RTU)
+      modbus: rs485serial
+      id: 101
+      device: /dev/ttyUSB0 # USB-RS485 Adapter Adresse
+      baudrate: 19200 # Prüfe die Geräteeinstellungen, typische Werte sind 9600, 19200, 38400, 57600, 115200
+      comset: "8E1" # Kommunikationsparameter für den Adapter
+
+      # RS485 via TCP/IP (Modbus RTU)
+      modbus: rs485tcpip
+      id: 101
+      host: 192.0.2.2 # Hostname
+      port: 502 # Port
diff --git a/templates/evcc.io/brands.json b/templates/evcc.io/brands.json
index 3b36acea2..3a2a5c705 100644
--- a/templates/evcc.io/brands.json
+++ b/templates/evcc.io/brands.json
@@ -35,6 +35,7 @@
   "LadeFoxx",
   "Mennekes",
   "NRGKick",
+  "OBO Bettermann",
   "OpenEVSE",
   "openWB",
   "Optec",