diff --git a/src/connector/grafana/tdengine/dist/datasource.js b/src/connector/grafana/tdengine/dist/datasource.js
index 8190394f9304dfc809b9c6c14dfcb1853fb15a72..73ba969b82c8cb56009c0e57b486b99ae5b48177 100644
--- a/src/connector/grafana/tdengine/dist/datasource.js
+++ b/src/connector/grafana/tdengine/dist/datasource.js
@@ -136,8 +136,10 @@ var GenericDatasource = exports.GenericDatasource = function () {
       if (options != null && options.range != null && options.range.to != null) {
         queryEnd = options.range.to.toISOString();
       }
-      var intervalMs = options.intervalMs || "20000";
-
+      var intervalMs = Math.max(options.intervalMs,15000);
+      if (isNaN(intervalMs)) {
+        intervalMs = 15000;
+      }
       intervalMs += "a";
       sql = sql.replace(/^\s+|\s+$/gm, '');
       sql = sql.replace("$from", "'" + queryStart + "'");
diff --git a/src/connector/grafana/tdengine/src/datasource.js b/src/connector/grafana/tdengine/src/datasource.js
index 08426bb3df6a8a8d78f6289284f56ac83c4713c8..3963849dd97243d8b99e661cf156dab7f563f77f 100644
--- a/src/connector/grafana/tdengine/src/datasource.js
+++ b/src/connector/grafana/tdengine/src/datasource.js
@@ -110,8 +110,10 @@ export class GenericDatasource {
     if (options != null && options.range != null && options.range.to != null){
       queryEnd = options.range.to.toISOString();
     }
-    var intervalMs = options.intervalMs || "20000";
-
+    var intervalMs = Math.max(options.intervalMs,15000);
+    if (isNaN(intervalMs)) {
+      intervalMs = 15000;
+    }
     intervalMs += "a";
     sql = sql.replace(/^\s+|\s+$/gm, '');
     sql = sql.replace("$from", "'" + queryStart + "'");