Deringer-Ney - Crown Height & Radius Tolerance Chart

Crown Height & Radius Tolerance of Radius Faced Contacts

Based on Contacts of 75% or More Silver in relay Applications. To find crown height for a known head dia. & radius, select head dia.; read down to intersection of radius. The crown height is given in the intersecting square. The standard tolerance for that radius is given ir. the column to the right by following the diagonal shaded area. Example: the crown height of a .500 R on a .156 diameter contact will be .006 with a tolerance of +.062.

Select type of load and voltage. Read down to amperes device will be required to carry Read across to Head Diameter column at right.

Contact head Diameter in Inches

Rad 1 US
(inch.)
	.062	.078	.094	.109	.126	.141	.156	.172	.187	.203	.218
.046	.012	.021	.047
.046	.012	.021	.047
.062	.008	.014	.021	.032	.062
.078	.007	.010	.016	.022	.031	.044	.078
.094	.005	.009	.013	.018	.024	.032	.042	.056	.094
.109	.005	.007	.011	.015	.020	.026	.033	.042	.053	.069	.109
.125	.004	.006	.009	.013	.017	.022	.027	.034	.042	.052	.064
.125	.004	.006	.009	.013	.017	.022	.027	.034	.042	.052	.064
.141	.004	.006	.008	.011	.015	.020	.024	.029	.036	.043	.052
.156	.003	.005	.007	.010	.013	.017	.021	.026	.031	.037	.045
.172	.003	.005	.007	.009	.012	.015	.019	.024	.028	.033	.039
.187	.003	.004	.006	.008	.011	.014	.017	.021	.025	.030	.035
.218	.002	.004	.005	.007	.009	.012	.014	.018	.021	.025	.031
.250	.002	.003	.004	.006	.008	.010	.013	.015	.018	.022	.025
.281	.002	.003	.004	.005	.007	.009	.011	.013	.016	.019	.022
.312	.002	.002	.004	.005	.006	.008	.010	.012	.014	.017	.020
.344	.001	.002	.003	.004	.006	.007	.009	.011	.013	.015	.018
.375	.001	.002	.003	.004	.005	.007	.008	.010	.012	.014	.016
.437	.001	.002	.003	.003	.004	.006	.007	.009	.010	.012	.014
.500	.001	.002	.002	.003	.004	.005	.006	.007	.009	.010	.012
.562	.001	.001	.002	.003	.003	.004	.005	.007	.008	.009	.011
.625	.001	.001	.002	.002	.003	.004	.005	.006	.007	.008	.010
.687	.001	.001	.002	.002	.003	.004	.004	.005	.006	.007	.008
.750	.001	.001	.001	.002	.003	.003	.004	.005	.006	.007	.008
.812	.001	.001	.001	.002	.002	.003	.004	.004	.005	.006	.007
.875	.001	.001	.001	.002	.002	.003	.003	.004	.005	.006	.007
.937	.001	.001	.001	.002	.002	.003	.003	.004	.005	.005	.006
1.000		.001	.001	.002	.002	.002	.003	.004	.004	.005	.006
1.125		.001	.001	.001	.002	.002	.003	.003	.004	.005	.005
1.250		.001	.001	.001	.002	.002	.002	.003	.004	.004	.005
1.375		.001	.001	.001	.001	.002	.002	.003	.003	.004	.004
1.500		.001	.001	.001	.001	.002	.002	.002	.003	.003	.004
1.750			.001	.001	.001	.001	.002	.002	.003	.003	.003
2.000			.001	.001	.001	.001	.002	.002	.002	.003	.003
2.500				.001	.001	.001	.001	.001	.002	.002	.002
3.000					.001	.001	.001	.001	.001	.002	.002