diff --git a/measure.py b/measure.py
index e84da6f6a1fcac4b2bda5e5c423b7671d7fedf82..917fc12a1d04544b71ff936956c704c58004cf98 100644
--- a/measure.py
+++ b/measure.py
@@ -65,14 +65,13 @@ class OhmPiHardware:
             sample+=1
             sleep_time = start_time + datetime.timedelta(seconds = sample * sampling_rate / 1000) - lap
             print(f'sleep_time: {sleep_time.total_seconds()} seconds')
-            time.sleep(sleep_time.total_seconds())
+            time.sleep(np.min([0, np.abs(sleep_time.total_seconds())]))
         self.readings = np.array(_readings)
 
     def _vab_pulse(self, vab, length, sampling_rate=None, polarity=None):
         """ Gets VMN and IAB from a single voltage pulse
         """
 
-
         if sampling_rate is None:
             sampling_rate = RX_CONFIG['sampling_rate']
         if polarity is not None and polarity != self.tx.polarity:
diff --git a/test_measure_with_ohmpi_card_3_15.py b/test_measure_with_ohmpi_card_3_15.py
index 187c630f66850cce394bd100203cad16ca2a6644..2ed4246437e2a21b1ffaf40908d7e5bea5c3aa35 100644
--- a/test_measure_with_ohmpi_card_3_15.py
+++ b/test_measure_with_ohmpi_card_3_15.py
@@ -3,5 +3,5 @@ change_config('config_ohmpi_card_3_15.py', verbose=False)
 from OhmPi.measure import OhmPiHardware
 
 k = OhmPiHardware()
-k._vab_pulse(vab=12, length=1., sampling_rate=10., polarity=1)
+k._vab_pulse(vab=12, length=1., sampling_rate=20., polarity=1)
 change_config('config_default.py', verbose=False)