IV–C–17

The purpose of this set is to determine the presence of and to identify any war gases in the atmosphere outside a fortification.

The front cover is embossed with the following: "Gasanzeiger (Fest)"; the nameplate riveted on the inside of the cover has the marking: "Gerät Gasanzeiger (Fest)".

The detector set is fixed in a metal case measuring 12.9 x 6.5 x 8.9 inches; the bot-tom (12.9 x 6.5) has four short rubber bumpers which act as legs for the case; the side with the embossed lettering is the front and is hinged at the top. It fastens shut at the bottom with two snap clasps. A web carrying strap is attached to the topy by two metal tabs which are bolted to the case. The hand operating wheel is on the outside of the right end; openings for the outlet and intake tubes are in the left end and the power in-takes socket is on the back side. On the inside of the front cover, there is a diagram naming the various parts of the apparatus and also a chart showing the color changes in the detector tubes.

The set has six separate airflow circuits, each with its own pump; these six circuits all connect into the common intake pipe as shown in the front of the diagram. The plastic bottom assemblies holding the lower of the rubber seats for the detector tubes are mar-ked the same as the detector tubes: one yellow band, two yellow bands, etc. The sixth has no marking and is probably meant for a newly developed tube. In the rear of the six positions for detector tubes there are six glass tubes connected to the outlet line by red rubber tubing. In each tube is a small glass bulb which bounces up and down indicating the flow or air through the individual circuite.

The pumps may be operated manually by the external hand wheel or by 220 volts DC or 220 volts AC, 50 cycle. There is a change-over switch, AC to DC and vice versa, pro-jecting in the front of the set between the second and third circuits. The set is usually attached to the intake and outlet pipes of the collective protector assembly by means of two cable hoses. When operated electrically, there is an automatic timing device on the left side of the case which can be set for 2, 3 or 4 minutes; 30 to 50 seconds before it shuts off, a warning bell rings. If operated manually, the hand wheel has to be turned over between 216 and 432 times. This will yield the same total air-flow through each cir-cuit as when the set is operated electrically.

IV–C–17