GB/T 27602-2011Measurement of radiofrequency sensitivity for industrial electric detonator (English PDF)

5.1 Basic radio frequency sensitivity test

5.1.1 Test location

All instruments, equipment, devices used in the test, except for the controller, shall be placed in a shielded chamber (see Figure 1); the ambient temperature of the test location shall be 16 °C ~ 32 °C; the relative humidity shall not exceed 75%. Actual environmental conditions shall be recorded during the measurement period.

5.1.2 Test frequency

At least six frequency points shall be selected for testing within the frequency range of

0.3 GHz ~ 18 GHz. Unless otherwise specified, six frequency points can be selected:

0.5 GHz, 1.8 GHz, 3.2 GHz, 5.5 GHz, 9.2 GHz, 15.0 GHz.

5.1.3 Test mode

The radio frequency (RF) sensitivity of industrial electric detonators in both foot-to- foot and foot-to-casing firing modes shall be tested.

5.2 Statistical RF sensitivity test

5.2.1 Test location

All instruments, equipment, devices used in the test, except for the controller, shall be placed in a shielded chamber (see Figure 1). The ambient temperature of the test location shall be 16 °C ~ 32 °C; the relative humidity shall not exceed 75%. Actual environmental conditions shall be recorded during the measurement period.

5.2.2 Test frequency

Based on the results of the basic RF sensitivity test, select the most sensitive frequency.

If this cannot be determined, the frequency of greatest interest can be used.

5.2.3 Test mode

Based on the results of the basic RF sensitivity test, select the most sensitive mode. If this cannot be determined, the test shall be conducted according to the test mode specified in 5.1.3.

6.1 Specimen quantity

6.1.1 Basic RF sensitivity test

Unless otherwise specified, at least 10 industrial electric detonator specimens conforming to GB 8031 shall be tested at each frequency point. Specimens that did not fire in the foot-to-shell firing mode test may be used in the foot-to-foot firing mode test, but a maximum of 5 specimens may be used.

6.1.2 Statistical RF sensitivity test

The number of industrial electric detonator specimens required for the statistical RF sensitivity test shall be determined according to the lifting method specified in GJB/Z 377A-1994.

6.2 Connecting leads

Connect the leads of all specimens according to the firing mode to be tested. For the foot-to-foot firing mode, the leads are the leads of the two bridge wires of the specimen;

for the foot-to-shell firing mode, the leads are the short-circuited leads and the wire connected to the specimen shell (i.e., the connector in Figure A.5). The lead length is (25 ± 0.5) mm; any excess shall be cut off.

6.3 Connection of specimen to N-50KK coaxial adapter

The connection between the specimen and the N-50KK coaxial adapter is detailed in

Appendix A.

7.1 Basic RF sensitivity test

7.1.1

Connect the RF sensitivity test system as shown in Figure 1. Turn on the power to all instruments; preheat and adjust according to the instrument instruction manual.

7.1.2

Set the controller's test switch to the power setting. The coaxial switch will then connect to the medium power meter.

7.1.3

Connect the N-50JJ coaxial adapter to the output of the matching device. Connect the other end of the N-50JJ coaxial adapter to the specimen already connected to the N-

50KK coaxial adapter (see Figure A.1); push it into the explosion-proof device.

7.1.4

Turn on the RF source high-voltage switch; select the test frequency; adjust the

RF source output power to 10 mW ~ 20 mW. Set the controller's test switch to the test setting. The coaxial switch will then connect to the matching device.

7.1.5

Adjust the matching device to achieve an incident power to reflected power ratio of 100:1, indicating that the matching is properly adjusted. Remove the test probes of the incident power meter and reflected power meter from the dual directional coupler.