AJAH.418266.007RE
5
2) trisodium phosphate or sodium hexametaphosphate (any detergent) – 10 - 20 g/l water
solution;
3) 5 % citric acid solution in rectified alcohol – for connectors and contacts.
1.2.23 Overall dimensions of the detector, not more than:
-
with handle …………………………………………………..………...... 316×240×290 mm;
-
with light-weight attachment fitting ………………………..………….... 254×256×350 mm;
-
with wall mounting …………………………...……………………….... 428×258×347 mm.
1.2.24 Weight of the detector without fitting/mounting, not more than ….……………. 11.5 kg.
1.2.25 Length of the connecting cable when used with twisted pair cable of category 5
type FTP-4 ..……………………………………..……………………………… not more than 1200 m.
1.2.26 Mean time before failure …………………...…………..……. not less than 10000 hours.
1.2.27 Mean life time ………………………………………..………..…. not less than 10 years.
1.3 Configuration
1.3.1 Detector consists of spherical neutron moderator with detector module placed inside it.
1.3.2 The following accessories are supplied by customer's request:
-
handle – for mobile versions of detectors;
-
attachment fitting or wall mounting – for stationary installed detectors;
-
cable plug RS10TV – for assembling a cable for connection with PC;
-
interface converter PI-02 – for connection to PC;
-
software “TETRA_Checker” developed for adjustment, calibration and verification of
detectors.
1.3.3 Cable for connection with PC is not included in the delivery kit, it is assembled by the
customer using the cable plug from the delivery kit in accordance with the wiring diagram
(Appendix B).
1.4 Design and operation
1.4.1 Detector module is comprised of:
-
scintillation detector based on LiF, enriched in
6
Li isotop to 85 %, and ZnS(Ag), placed in
the plexiglass for conversion of slow/thermal neutrons into scintillations (flashes of light);
-
PMT (photomultiplier tube) – for registration of scintillations;
-
high voltage converter – for high voltage supply to the PMT;
-
amplifier-discriminator – for amplifying and selection by amplitude of pulses from the PMT;
-
microcontroller unit – for linearization and normalization of measurement results and data
transfer to the external device.
1.4.2 Neutron moderator is intended for deceleration and thermalization of fast neutrons.
Neutron moderator can be of portable version with handle, alternatively it can be equipped with
a light-weight attachment fitting or a wall mounting.
Outline drawing of the neutron moderator are presented in the Appendix C.
1.4.3 Operating principle of detectors is based on conversion of the ionizing radiation energy
into electric pulses.
By request of an external device, detectors return measured value of AEDR
10
*
at the time
of request, calculated by the formula
MN
1
N
K
10
*
(1.2)
where K – sensitivity coefficient, Sv h
-1
s;
N – frequency of pulses, s
-1
;
M – “dead time”, s.
