diff --git a/sequence/utils/log.py b/sequence/utils/log.py
index 04ef5e4f..33d9f272 100644
--- a/sequence/utils/log.py
+++ b/sequence/utils/log.py
@@ -20,7 +20,7 @@ def _init_logger():
     return lg
 
 
-logger = _init_logger()
+logger = _init_logger()  # global logger
 # LOG_FORMAT = '{asctime}  {simtime:<20,} {levelname:7} {module:20} {message}'
 LOG_FORMAT = '{simtime:<20,} {levelname:7} {module:20} {message}'   # no asctime
 _log_modules = []
@@ -40,6 +40,10 @@ def set_logger(name: str, timeline, logfile="out.log"):
     global logger
     logger = logging.getLogger(name)
 
+    # remove existing handleers
+    for h in logger.handlers:
+        logger.removeHandler(h)
+
     handler = logging.FileHandler(logfile)
     fmt = logging.Formatter(LOG_FORMAT, style='{')
     f = ContextFilter(timeline)