diff --git a/bluecellulab/cell/injector.py b/bluecellulab/cell/injector.py
index a49a9fe..a881637 100644
--- a/bluecellulab/cell/injector.py
+++ b/bluecellulab/cell/injector.py
@@ -189,7 +189,7 @@ def add_voltage_clamp(
         vclamp.amp1 = level
 
         if durations is not None and levels is not None:
-            if len(levels) != len(durations) - 1:
+            if len(levels) != len(durations):
                 raise BluecellulabError("Inconsistent durations and levels for seclamp.")
 
             voltage_vec = h.Vector(levels)
diff --git a/tests/test_cell/test_injector.py b/tests/test_cell/test_injector.py
index eb06547..1d337b3 100644
--- a/tests/test_cell/test_injector.py
+++ b/tests/test_cell/test_injector.py
@@ -143,7 +143,7 @@ def test_multilevel_voltage_clamp(self):
         amp = 10
         stop_time = 10
         voltages = [20, 30]
-        durations = [2, 3, 5]
+        durations = [2, 3]
         rs = 1
         seclamp_obj = self.cell.add_voltage_clamp(
             stop_time=stop_time, level=amp, rs=rs, levels=voltages, durations=durations,
@@ -158,6 +158,7 @@ def test_multilevel_voltage_clamp(self):
         self.sim.run(10, dt=0.2, cvode=False)
         voltage_rec = np.array(v_rec.to_python())
         # has to add one 10 at the beginning for t=0
+        # last value (30) will last until clamp is off
         assert (voltage_rec == np.array(
             [
                 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10,  # 10 + 1 extra for t=0