diff --git a/util/modbus/modbus_test.go b/util/modbus/modbus_test.go
new file mode 100644
index 000000000..c462f4958
--- /dev/null
+++ b/util/modbus/modbus_test.go
@@ -0,0 +1,30 @@
+package modbus
+
+import "testing"
+
+func TestParsePoint(t *testing.T) {
+	tc := []struct {
+		in           string
+		model, block int
+		point        string
+		err          bool
+	}{
+		{"103:W", 103, 0, "W", false},
+		{"802:1:V", 802, 1, "V", false},
+		{"802::V", 802, 1, "V", true},
+	}
+
+	for _, tc := range tc {
+		t.Log(tc)
+
+		model, block, point, err := ParsePoint(tc.in)
+
+		if (err != nil) != tc.err {
+			t.Errorf("unexpected error: %d:%d:%s %v", model, block, point, err)
+		}
+
+		if !tc.err && (model != tc.model || block != tc.block || point != tc.point) {
+			t.Errorf("unexpected result: %d:%d:%s", model, block, point)
+		}
+	}
+}