Electrically operated device, especially duplicating device, with a receptacle to accommodate fluid for the chemical treatment of objects

An electrically operated offset printer including means for etching offset printing films, said means for etching comprising a dip tank having means for passing said offset printing films therethrough, a storage tank for storing the etching fluid, a supply conduit connecting said dip tank and said storage tank for passing etching fluid from said storage tank to said dip tank, pump means for causing etching fluid to pass from said storage tank to said dip tank, an automatic charging and metering unit for controlling said pump means to pump etching fluid into said dip tank when the fluid level in the dip tank is below a predetermined level, and a drain conduit, connecting the storage tank with the dip tank, for draining the etching fluid from the dip tank, said drain conduit including a solenoid valve which is adapted to be opened for draining the etching fluid from the dip tank, whereby the dip tank can be drained when the printer is turned off and the dip tank will be filled to operating level when the printer is operated, without continuous operation of said pump means.