diff --git a/tests/test_concurrency/test_schedulerbase.py b/tests/test_concurrency/test_schedulerbase.py
new file mode 100644
index 000000000..7e6625c32
--- /dev/null
+++ b/tests/test_concurrency/test_schedulerbase.py
@@ -0,0 +1,51 @@
+import unittest
+from datetime import timedelta
+
+from rx.internal.constants import DELTA_ZERO, UTC_ZERO
+from rx.concurrency.schedulerbase import SchedulerBase
+
+
+class TestSchedulerBase(unittest.TestCase):
+
+    def test_base_to_seconds(self):
+        val = SchedulerBase.to_seconds(0.0)
+        assert val == 0.0
+        val = SchedulerBase.to_seconds(DELTA_ZERO)
+        assert val == 0.0
+        val = SchedulerBase.to_seconds(UTC_ZERO)
+        assert val == 0.0
+
+    def test_base_to_datetime(self):
+        val = SchedulerBase.to_datetime(0.0)
+        assert val == UTC_ZERO
+        val = SchedulerBase.to_datetime(DELTA_ZERO)
+        assert val == UTC_ZERO
+        val = SchedulerBase.to_datetime(UTC_ZERO)
+        assert val == UTC_ZERO
+
+    def test_base_to_timedelta(self):
+        val = SchedulerBase.to_timedelta(0.0)
+        assert val == DELTA_ZERO
+        val = SchedulerBase.to_timedelta(DELTA_ZERO)
+        assert val == DELTA_ZERO
+        val = SchedulerBase.to_timedelta(UTC_ZERO)
+        assert val == DELTA_ZERO
+
+    def test_base_normalize_float(self):
+        val = SchedulerBase.normalize(-1.0)
+        assert val == 0.0
+        val = SchedulerBase.normalize(0.0)
+        assert val == 0.0
+        val = SchedulerBase.normalize(1.0)
+        assert val == 1.0
+
+    def test_base_normalize_delta(self):
+        DELTA_ONE = timedelta(seconds=1.0)
+        val = SchedulerBase.normalize(-DELTA_ONE)
+        assert val == DELTA_ZERO
+        val = SchedulerBase.normalize(DELTA_ZERO)
+        assert val == DELTA_ZERO
+        val = SchedulerBase.normalize(DELTA_ONE)
+        assert val == DELTA_ONE
+
+