diff --git a/pvmismatch/pvmismatch_lib/pvstring.py b/pvmismatch/pvmismatch_lib/pvstring.py
index 3cfa028..02b32ea 100644
--- a/pvmismatch/pvmismatch_lib/pvstring.py
+++ b/pvmismatch/pvmismatch_lib/pvstring.py
@@ -90,11 +90,19 @@ def setSuns(self, Ee):
             for pvmod in iter(self.pvmods):
                 pvmod.setSuns(Ee)
         else:
-            for pvmod, cell_Ee in Ee.iteritems():
-                if hasattr(cell_Ee, 'keys'):
-                    self.pvmods[pvmod].setSuns(**cell_Ee)
-                else:
-                    self.pvmods[pvmod].setSuns(*cell_Ee)
+            try:
+                for pvmod, cell_Ee in Ee.iteritems():
+                    if hasattr(cell_Ee, 'keys'):
+                        self.pvmods[pvmod].setSuns(**cell_Ee)
+                    else:
+                        try:
+                            self.pvmods[pvmod].setSuns(*cell_Ee)
+                        except TypeError:
+                            self.pvmods[pvmod].setSuns(cell_Ee)
+            except AttributeError:
+                Ee = Ee[0]
+                for pvmod in iter(self.pvmods):
+                    pvmod.setSuns(Ee)
         # update modules
         self.Istring, self.Vstring, self.Pstring = self.calcString()
 
diff --git a/pvmismatch/tests/test_pvcell.py b/pvmismatch/tests/test_pvcell.py
index 84d5119..ce395a6 100644
--- a/pvmismatch/tests/test_pvcell.py
+++ b/pvmismatch/tests/test_pvcell.py
@@ -59,7 +59,7 @@ def test_calc_series():
     # noinspection PyTypeChecker
     ok_(np.allclose(i, iv[0]))
     # noinspection PyTypeChecker
-    ok_(np.allclose(v, iv[1]))
+    ok_(np.allclose(v, iv[1], rtol=1e-4))
     return i, v
 
 
diff --git a/pvmismatch/tests/test_setsuns.py b/pvmismatch/tests/test_setsuns.py
new file mode 100644
index 0000000..73c0046
--- /dev/null
+++ b/pvmismatch/tests/test_setsuns.py
@@ -0,0 +1,50 @@
+"""
+Test for setSuns method.
+
+Bennet Meyers 10/10/16
+"""
+
+import numpy as np
+from nose.tools import ok_
+from pvmismatch.pvmismatch_lib.pvsystem import PVsystem
+
+
+def test_basic():
+    pvsys = PVsystem()
+    pvsys.setSuns(.75)
+    ok_(np.isclose(pvsys.Pmp, 23907.936630685774))
+
+
+def test_dictionary():
+    pvsys = PVsystem()
+    Ee = {1: {3: {'cells': np.arange(30), 'Ee': [.25] * 30}}}
+    pvsys.setSuns(Ee)
+    ok_(np.isclose(pvsys.Pmp, 31618.1813179655))
+
+
+def test_set_mod_1():
+    pvsys = PVsystem()
+    Ee = {1: {3: [.2], 0: [.1]}}
+    pvsys.setSuns(Ee)
+    ok_(np.isclose(pvsys.Pmp, 29566.303088387336))
+
+
+def test_set_mod_2():
+    pvsys = PVsystem()
+    Ee = {1: {3: .2, 0: .1}}
+    pvsys.setSuns(Ee)
+    ok_(np.isclose(pvsys.Pmp, 29566.303088387336))
+
+
+def test_set_str_1():
+    pvsys = PVsystem()
+    Ee = {1: [.1]}
+    pvsys.setSuns(Ee)
+    ok_(np.isclose(pvsys.Pmp, 29136.544447716446))
+
+
+def test_set_str_2():
+    pvsys = PVsystem()
+    Ee = {1: .1}
+    pvsys.setSuns(Ee)
+    ok_(np.isclose(pvsys.Pmp, 29136.544447716446))