diff --git a/CHANGES_NEXT_RELEASE b/CHANGES_NEXT_RELEASE
index 1410fcbd..b51f5812 100644
--- a/CHANGES_NEXT_RELEASE
+++ b/CHANGES_NEXT_RELEASE
@@ -1,4 +1,5 @@
 - Add: allow access entities using NGSIv2 API for non_signal rules (new setting nonSignalByAPI / PERSEO_CHECK_NON_SIGNAL_BY_API) (#549)
 - Remove support for ngsv1 notifications (#714)
 - Remove ngsiv1 support for updateAction (#714)
+- Fix: check timer string in lower case in TimedRule checker
 
diff --git a/lib/models/rules.js b/lib/models/rules.js
index 9ae43c46..ab6f75eb 100644
--- a/lib/models/rules.js
+++ b/lib/models/rules.js
@@ -85,7 +85,7 @@ function isTimedRule(rule) {
     // Detect timed rules, taken from perseo-core
     // https://github.com/telefonicaid/perseo-core/blob/master/perseo-main/src/main/java/com/telefonica/iot/perseo/TimeRulesStore.java#L110
     return (
-        (rule.text && rule.text.includes('timer:')) ||
+        (rule.text && rule.text.toLowerCase().includes('timer:')) ||
         (rule.text &&
             rule.text.toLowerCase().includes('match_recognize') &&
             rule.text.toLowerCase().includes('interval'))