diff --git a/ohmpi/ohmpi.py b/ohmpi/ohmpi.py
index c6a7a13781945b6a412f5c96abbe338adc529a8a..2f628fefd6ae5c90d383e771085992d1b76c8ab2 100644
--- a/ohmpi/ohmpi.py
+++ b/ohmpi/ohmpi.py
@@ -508,23 +508,23 @@ class OhmPi(object):
         # check arguments
         if quad is None:
             quad = np.array([0, 0, 0, 0])
-        if nb_stack is None:
+        if nb_stack is None and 'nb_stack' in self.settings:
             nb_stack = self.settings['nb_stack']
-        if injection_duration is None:
+        if injection_duration is None and 'injection_duration' in self.settings:
             injection_duration = self.settings['injection_duration']
-        if duty_cycle is None:
+        if duty_cycle is None and 'duty_cycle' in self.settings:
             duty_cycle = self.settings['duty_cycle']
-        if tx_volt is None:
+        if tx_volt is None and 'tx_volt' in self.settings:
             tx_volt = self.settings['tx_volt']
-        if strategy is None:
+        if strategy is None and 'strategy' in self.settings:
             strategy = self.settings['strategy']
-        if vab_max is None:
+        if vab_max is None and 'vab_max' in self.settings:
             vab_max = self.settings['vab_max']
-        if iab_max is None:
+        if iab_max is None and 'iab_max' in self.settings:
             iab_max = self.settings['iab_max']
-        if vmn_max is None:
+        if vmn_max is None and 'vmn_max' in self.settings:
             vmn_max = self.settings['vmn_max']
-        if vmn_min is None:
+        if vmn_min is None and 'vmn_min' in self.settings:
             vmn_min = self.settings['vmn_min']
         bypass_check = kwargs['bypass_check'] if 'bypass_check' in kwargs.keys() else False
         d = {}
diff --git a/settings/default.json b/settings/default.json
index dce3250ff38f4ac4f36696dbe70bb9cf097ef697..a0178639f1a9f15c93c2345546aabf3cba6f526f 100644
--- a/settings/default.json
+++ b/settings/default.json
@@ -7,10 +7,6 @@
     "tx_volt": 5,
     "duty_cycle": 0.5,
     "strategy": "constant",
-    "iab_max": null,
-    "vab_max": null,
-    "vmn_max": null,
-    "vmn_min": null,
     "fw_in_csv": true,
     "fw_in_zip": true,
     "export_path": "data/measurements.csv"