The invention discloses a total
hydrocarbon tester having the on-line
attenuation function. The tester comprises a sampling
pipe, a pump, a
hydrogen flame ionization detector, a
compressed air bottle and a
mixed gas chamber. An input end of the
mixed gas chamber is connected with the sampling
pipe, the other input end of the
mixed gas chamber is connected with an air
pipe, and the air pipe is connected with the
compressed air bottle and provided with an
air flow control device. The output end o the mixed
gas chamber is connected with the pump through a mixed gas flow control device, and the pump is connected with the
hydrogen flame ionization detector. Sample gas enters the mixed
gas chamber, is mixed with clean air and reaches the
hydrogen flame ionization detector under the action of the pump, and the
hydrocarbon content of the sample gas is tested. The mixed gas flow control device and the
air flow control device cooperate to control the proportion of the sample gas to the clean air, and the on-line
attenuation function is achieved. By means of the total
hydrocarbon tester, the concentration of hydrocarbon in the sample gas entering the hydrogen
flame ionization detector is lowered in a quantitative mode, and shutdown of the tester due to overload or insufficient
oxygen in the sample gas or other reasons is avoided.