introduction to the catalogue - Ilme SpA

limit current curves of the insertsCK series - CKS seriesgeneralcurvesload curvesload curvesThe current carrying capacity possible in the connectors is variable. It reduces with the increase of the number of polesand the temperature of the environment in which the connector is installed and is determined by the thermalproperties of the materials used for the contacts and the insulating parts as well as by the type of conductor used.The current carrying capacity is obtained from the load curves which are constructed according to standard IEC60512-5-2 for currents circulating simultaneously in all poles.The limit current curves express current values that determine the achievement of the highest limit temperature of thematerials. The choice of the permanent load applicable on the contacts must be made within the field of operationpossible delimited by the above curves.Since the use of the connectors at the limit of the values of their characteristics is not recommended, the base curveis derated. The reduction of the load curves to 80% defines the correction curve where both the maximum contactresistance permissible and the inaccuracy of the temperature measurements are sufficiently borne in consideration.The correction curve represents the final limit current curve (load curve) as defined by standard IEC 60512-5-2.It therefore bears in consideration the difference between the various connectors, as well as errors in thetemperature measurements.All the load curves presented herebelow include the corrections.working current (A)3025201510500diagram CK 03 poles1,0 mm 2 1,5 mm 2 2,5 mm 20,5 mm 210 20 30 40 50 60 70 80 90 100 110ambient temperature (°C)diagram CK 04 polesenvironment30I (A)temperaturelimitlimit temperatureof the materialsTI n (base curve)0,8 x I nworking current (A)252015101,0 mm 2 1,5 mm 2 2,5 mm 2maximum load current (A)temperaturefield allowedload curveambient temperature (°C)working current (A)50030252015100,5 mm 210 20 30 40 50 60 70 80 90 100 110ambient temperature (°C)diagram CKS 03 poles1,5 mm 2 2,5 mm 21,0 mm 2Legend:Maximum load current (A): value for which the connector reaches the limit temperature of the material at theenvironmental temperature, intersected on the load curve.Limit temperature of the materials: value determined by the characteristics of the materials used. The sum ofthe environmental temperature and the increase of the simbolo ΔT temperature caused by the passage of thecurrent must not exceed the limit temperature of the materials.Environment temperature limit: the environmental conditions must not exceed this value. It may be know anddetermines the maximum load current, or may be obtained directly from the load curve.Base curve: set of current and temperature values obtained from laboratory tests and influenced by the connector’scharacteristics (number of poles, construction shape, thermal conductivity of the materials, etc.) and the section ofthe conductor used.Load curve (limit current curve): obtained from the base curve via the safety coefficient.ΔT (overtemperature): temperature increase produced by a permanent current circulating through all the poles ofa connector coupling; difference between the limit temperature of the materials and the environmental temperatureobtained on the limit current curve.working current (A)50010 20 30 40 50 60 70 80 90 100 110 120 130ambient temperature (°C)diagram CKS 04 poles30252015101,5 mm 2 2,5 mm 21,0 mm 250010 20 30 40 50 60 70 80 90 100 110 120 130ambient temperature (°C)28