diff -r c9101b2eeb6a -r fa6e702d0d24 www/ispindel/index.php
--- a/www/ispindel/index.php	Mon Jan 06 14:20:17 2020 +0100
+++ b/www/ispindel/index.php	Mon Jan 06 15:07:40 2020 +0100
@@ -15,7 +15,10 @@
 	$interval = $data['interval'];
         if (floatval($data['battery']) < 3.3) {
                 $alarm += 4;
-		$interval = 3600; // 3600 seconds when the battery is low.
+		if (($interval * 3) < 3600)
+			$interval = 3600; // at least 3600 seconds when the battery is low.
+		else
+			$interval = $interval * 3;
 	}
 
 	$uuid = 'c0ffeeee-cafe-dead-beef-' . sprintf("%06x", 0xffffff - floatval($data['ID'])) . sprintf("%06x", floatval($data['ID']));