diff --git a/scheduler/schedule.cpp b/scheduler/schedule.cpp
index e648b2a..d2d3873 100644
--- a/scheduler/schedule.cpp
+++ b/scheduler/schedule.cpp
@@ -144,7 +144,7 @@ int SensorScheduler::GetNextDuration(int short_addr) {
     long next_ts = CalcNextTimestamp(id);
     int duration = next_ts - current_ts;
     zlog_debug(zct, "[%d] next duration is %d", id, duration);
-    return 0; 
+    return duration; 
 }
 
 long SensorScheduler::GetBaseTimestamp(int short_addr) {