diff --git a/syslib/utils_os.robot b/syslib/utils_os.robot
index ac61680..1f28d7c 100755
--- a/syslib/utils_os.robot
+++ b/syslib/utils_os.robot
@@ -426,7 +426,7 @@
 
 Check HTX Run Status
     [Documentation]  Get HTX exerciser status and check for error.
-    [Arguments]  ${sleep_time}=${EMPTY}
+    [Arguments]  ${sleep_time}=${0}
 
     # Description of argument(s):
     # sleep_time  The amount of time to sleep after checking status.
@@ -442,7 +442,7 @@
     Should Contain  ${htx_errlog}  file </tmp/htxerr> is empty
     ...  msg=HTX geterrorlog was not empty.
 
-    Return From Keyword If  ${sleep_time} == ${EMPTY}
+    Return From Keyword If  ${sleep_time} == ${0}
 
     Run Key U  Sleep \ ${sleep-time}