The commutation characteristics of TPI-type pseudospark switches, depending on the parameters of trigger circuits, are studied. An influence of the trigger pulse rise time on the pseudosparks time jitter is explored. It has been shown that the pseudospark switches can be triggered on a pre-ionization electrode with a cathode and a grid, simultaneously grounded. The double and the triple gapped deuterium and hydrogen switches were explored. The time jitter values of 1-2 ns on the deuterium switches triggered on the pre-ionization electrode have been achieved.