To study the safety of pulse excitation of hot bridge wire EED， we established a numerical model for the temperature rise of the hot bridge wire EED， and the ignition criterion of hot bridge wire EED was obtained. Based on the above， we designed the calculation procedure for the critical ignition current of the hot bridge wire EED and revealed the influence of single pulse and pulse train current excitation parameters on the critical ignition current of hot bridge wire EED. The results showed that under single pulse excitation and when the pulse width was less than 5 μs， the ignition energy of the hot bridge wire EED was fixed， which suggested that the bridge wire-reagent system was in an adiabatic state. So the ignition state was related to the energy input to the bridge wire. However， when the pulse width was greater than 15 ms， the critical ignition current of the hot bridge wire EED was fixed. So the ignition state was related to the electric power of the bridge wire. Another difference was that under narrow pulse train current excitation， the time constant of the curve for critical ignition current with repetition period was independent of the pulse width. Furthermore， when the repetition period was greater than 1.25 ms， the bridge wire-reagent system exhibited no thermal accumulation effect， and the critical ignition current was the same as the single pulse current excitation. However， when the repetition period was lower than 1.25 ms， the bridge wire-reagent system exhibited the thermal accumulation effect， which resulted in rapid decrease of the critical ignition current as the repetition period decreased.