Reference curves inductive circuits

Figure 6.165 Inductance L (in H) versus minimum igniting current I (in A) for Groups IIA/B/C. Inductive circuits, circuit test voltage 24 V DC (according to IEC 60079-11 and EN 50020). The energy levels indicated refer to the constant energy portion of the curve.

To a certain extent, the interconnection inherits the poorest properties of both apparatus. If during the design of a category ia circuit capacitance C and inductance L are examined simultaneously (for zone 0 application), then various combinations (CG, L0) are given in the certificate (Fig. 6.220) for the most part. As a rule, these values are smaller than those derived from the reference curves. 

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