Reservoirs are primarily intended for use in delay circuits in conjuction with flow regulators snd pressure-sensitive valves. The circuit is usually arranged so that the reservoir is connected to the inlet port of an ZNCN/151 pilot sequence valve and is slowly charged with pressure air admitted by a flow regulator ZNCN/650. When the pressure in the reservoir has built up to a percentage of the supply pressure, the pilot sequence valve opens to admit a pilot signal to the valve controling the cylinder or the pneumatic device. The timing ranges quoted are necessarily modified by the valume of the associated piping.

The circuit described are intended to provide a delay, not an accurate timing. The repeat accuracy is approximately 5%.