Electric detonator series firing

A Minimum lag time 6 Minimum excitation time C Maximum excitation time X Minimum firing current for single detonator V Minimum series tiring current Fig. 10.7. Series firing of electric detonators. 

Taylor Gay (Ref 36, pp 62-4), discuss "principles of series "shotfiring" where they explain why the current needed to fire a series should be greater than that required to fire a single electric detonator. If a uniform direct... 

The firing characteristics of commercial electric detonators are shown in Ref 36, p 64, Fig 11, given here as Fig 13. The curve APB of Fig shows the relation between current t and "minimum lag time" for the most rapid detonator in the series, while the curve CPD shows the corresponding relation between current and "maximum excitation time " for the least sensitive detonator of the series. From the curve it can be seen that with current ij, the most rapid detonator will break the circuit in T4 milliseconds, whereas the least sensitive detonator requires at least T5 millisecs of current flow to enable it to fire. At a higher current 12, however, the excitation time T, is less than time T2 which is allowed by the most rapid detonator, and hence the least... 

Fig 13 THEORY OF SERIES FIRING WITH TWO TYPES OF ELECTRIC DETONATORS... 

For firing successfully a series of detonators it is required that the shortest Tag time" of any of them must exceed the longest "excitation time "of any of them. In other words, every one of the detonators must receive the full quota of electric energy to cause its ignition before any single one of them has completed its "lag time"... 

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