From 7bf64c56b78a46bb0ce685bc0c91c1b896fd86c9 Mon Sep 17 00:00:00 2001
From: Timothy Nunn <timothy.nunn@ukaea.uk>
Date: Wed, 29 Oct 2025 09:57:37 +0000
Subject: [PATCH] Correct constraint 64

---
 process/constraints.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/process/constraints.py b/process/constraints.py
index 316f3d0f74..b72e12f3c5 100644
--- a/process/constraints.py
+++ b/process/constraints.py
@@ -1660,7 +1660,7 @@ def constraint_equation_64():
     """
     cc = (
         data_structure.physics_variables.zeff
-        / data_structure.constraint_variables.fzeff_max
+        / data_structure.constraint_variables.zeff_max
         - 1.0 * data_structure.constraint_variables.fzeff_max
     )
     return ConstraintResult(