diff --git a/src/lib/device.ts b/src/lib/device.ts
index 578441910360248dce0bd4f0b1f791d7cb71880b..18f6f91d2fd9f78fbb0bf953734e3a6fdfc12d6f 100644
--- a/src/lib/device.ts
+++ b/src/lib/device.ts
@@ -79,7 +79,7 @@ export default abstract class Device extends js.global.EventEmitter {
 
 	protected log(level: number, msg: string, time?: number, source?: string) {
 		let _msg = '';
-		if (js.global.server === undefined) msg += js.global.strftime('%Y-%m-%d %H:%M:%S ');
+		if (js.global.server === undefined) _msg += js.global.strftime('%Y-%m-%d %H:%M:%S ');
 		_msg += `${this.deviceTag} device ${this.configId}: ${msg}`;
 		this.emit('log', level, _msg, time, source);
 	}