With the permissible degree of filling in the tank you define theresponse level of the Overfill Protection System (see Fig. 4).

The permissible degree of filling is calculated in accordance with the German Technical Rules for Combustible Liquids TRbF 280, para. 2.2. Take the operating delay time into account (see Section 7 "Technical data").

The respective probe length (Z) is permanently marked with a punch above the marking groove at the top of the probe. It is the distance between the marking groove and the threshold point of the level detector (see Fig. 4).To set the response length (L) as the distance between the hexa-gonal support of the screw-in body and the marking groove on the protective sleeve of the sensor at the bottom of the level detector, proceed as follows (see Fig. 4):•Calculate the response length (L) depending on the tankdimensions and the response level (A). L = (H - A) + S•Set the calculated response length (L) on the level detector.

Once the level detector has been fitted, the setting ofresponse length (L), using the reference dimension (Y) (=distance between the marking groove at the top of the probe tube and the hexagonal support of the screw-in body) and the punched probe length (Z), can be checked to make sure it is correct, without removing the sensor. L = Z - Y

To fix the probe tube in place proceed as follows:•Tighten up the stuffing box screw of the screw-in body andlock it by tightening up the lock screw.•Provide the screw-in thread with suitable, resistant sealingmaterial and screw it into the special tank sleeve.

Since the response length (L) of the Type 76 M level detector cannot be varied (probe tube is fixed inside the screw-in body), this dimension has to be calculated and specified using the tank dimensions and the accurately calculated response length (A) before placing the order. The response length is permanently marked with a punch on the screw-in body of the level detector.
Overfill Protection System Type 76/NB 220 13