摘要 |
A metering apparatus is provided including a metering pump 7 to which the output signal of a flow meter 2 is fed. For the protection against overdosing electronic monitoring means 10 is provided which turns off the electronic metering control means (4) if the electronic metering control means 4 or the metering pump 7, respectively, of the metering apparatus does not operate properly, and thereby prevents overdosing. A comparator 19 in the monitoring device 10 checks for conformity or correlation between at least two of its input signals to apply an interrupt signal to device 4. <IMAGE> |