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. 

The curves of Fig. 10.7 apply only to fuseheads made to the same specification. If fuseheads are made with different bridgewires or different flashing dips, the corresponding curves could be completely different and there may be no point at which the minimum lag time of one type of detonator exceeds the maximum excitation time of the other. Under these conditions series firing would not be practicable and it follows that it is not feasible to use different types of detonators in a single series firing circuit. 

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

Two types, FMU-7/B and FMU-7AB, similar in construction and function, are described in Ref 51a, p 5-50 and are shown here in Fig 5 25. They are used in conjunction with FMU-7 series fuzes and cable assemblies in the BLU series fire bombs... 

Cable Assemblies FMU-7B and FMU-7A/B are electrical cables 0.19-inches in diam and 76-in long used to interconnect the FMU-7 series fuzes with the FMU-7 series initiators on BLU series fire bombs (Ref 51a, p 5-51)... 

Te, Mg, Se or Zr, or a mixture of smokeless powders. It is suitable for electric squibs. Tire mixture is heated by means of a bridge wire of Ni-Cr alloy with a diam of at least 0.00225 , whereby certainty of firing is assured under conditions prevailing in series firing USP 2228339... 

A study was undertaken with a view to determine the basic mechanism of failure in series firing ability. The excitation time, transfer time and total rime of three different types of squibs (i) with LMNR as base (ii) with Lead Dimtro-ortho-cresol (LDNOC) as base and (in.) with charcoal plus potassium chlorate as base were determined... 

Reliable series firings can be achieved if these considerations are taken into account. The advantages of series firings are that circuit current is lower than in parallel firing. This means that switches, voltage dividers, reference diodes, etc., can all be at lower current ratings, hence, smaller and probably less expensive. Also electrical cable and other conductors can be smaller, and usually hook-up is simpler and fewer connectors can be used. 

Therefore, the constant relation between fire/water = air/water = water/ land actually involves the constant between successive terms of the series, fire, air, water, and land thus defining the geometric proportions of the universe (Figure P.l). 

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