diff --git a/proseco/catalog.py b/proseco/catalog.py
index 7e2885eb..3e6ad22b 100644
--- a/proseco/catalog.py
+++ b/proseco/catalog.py
@@ -161,7 +161,7 @@ def get_effective_t_ccd(t_ccd):
     :param t_ccd:
     :return:
     """
-    t_limit = ACA.aca_t_ccd_planning_limit
+    t_limit = ACA.aca_t_ccd_penalty_limit
     if t_ccd > t_limit:
         return t_ccd + 1 + (t_ccd - t_limit)
     else:
@@ -219,7 +219,7 @@ def set_attrs_from_kwargs(self, **kwargs):
 
         In this ACATable object:
         - t_ccd_eff_{acq,guide} are the effective T_ccd values which are adjusted
-          if the actual t_ccd{acq,guide} values are above ACA.aca_t_ccd_planning_limit.
+          if the actual t_ccd{acq,guide} values are above ACA.aca_t_ccd_penalty_limit.
         - t_ccd_{acq,guide} are the actual (or predicted) values from the call
 
         The downstream AcqTable, GuideTable, and FidTable are initialized with the
diff --git a/proseco/characteristics.py b/proseco/characteristics.py
index 6f00c3cd..67188fc4 100644
--- a/proseco/characteristics.py
+++ b/proseco/characteristics.py
@@ -29,8 +29,9 @@
 col_spoiler_mag_diff = 4.5
 col_spoiler_pix_sep = 10  # pixels
 
-# ACA T_ccd planning limit (degC)
-aca_t_ccd_planning_limit = -8.8
+# ACA T_ccd penalty limit (degC).
+# Above this limit a temperature "penalty" is applied via get_effective_t_ccd()
+aca_t_ccd_penalty_limit = -8.8
 
 # Dark current that corresponds to a 5.0 mag star in a single pixel.  Apply
 # this value to the region specified by bad_pixels.
diff --git a/proseco/tests/test_catalog.py b/proseco/tests/test_catalog.py
index c039d5cf..3fb80fef 100644
--- a/proseco/tests/test_catalog.py
+++ b/proseco/tests/test_catalog.py
@@ -304,14 +304,14 @@ def test_big_sim_offset():
 def test_calling_with_t_ccd_acq_guide(call_t_ccd):
     """Test that calling get_aca_catalog with t_ccd or t_ccd_acq/guide args sets all
     CCD attributes correctly in the nominal case of a temperature
-    below the planning limit.
+    below the penalty limit.
 
     """
     dark = DARK40.copy()
     stars = StarsTable.empty()
     stars.add_fake_constellation(mag=8.0, n_stars=8)
 
-    t_ccd = np.trunc(ACA.aca_t_ccd_planning_limit - 1.0)
+    t_ccd = np.trunc(ACA.aca_t_ccd_penalty_limit - 1.0)
 
     if call_t_ccd:
         # Call with just t_ccd=t_ccd
@@ -355,13 +355,13 @@ def test_calling_with_t_ccd_acq_guide(call_t_ccd):
 @pytest.mark.parametrize('t_ccd_case', t_ccd_cases)
 def test_t_ccd_effective_acq_guide(t_ccd_case):
     """Test setting of effective T_ccd temperatures for cases above and
-    below the planning limit.
+    below the penalty limit.
 
     """
     stars = StarsTable.empty()
     stars.add_fake_constellation(mag=8.0, n_stars=8)
 
-    t_limit = ACA.aca_t_ccd_planning_limit
+    t_limit = ACA.aca_t_ccd_penalty_limit
 
     t_offset, t_penalty_acq, t_penalty_guide = t_ccd_case
     # Set acq and guide temperatures different