diff --git a/ilt1000.py b/ilt1000.py
index a913092..b889960 100755
--- a/ilt1000.py
+++ b/ilt1000.py
@@ -33,8 +33,6 @@ class CommandError(Error):
 # captureflash (SPEC ERROR: doc description missing)
 # getflash
 
-# setirrthresholdlow
-
 # setcurrentloop
 
 # setuserdark
@@ -211,6 +209,9 @@ class ILT1000(object):
   def GetIrradiance(self):
     return float(self._SendCommand('getirradiance'))
 
+  def SetIrradianceThresholdLow(self, value):
+    self._SendCommandOrDie('setirrthresholdlow %.2e' % value)
+
   def GetIrradianceThresholdLow(self):
     return float(self._SendCommand('getirrthresholdlow'))