Endress+Hauser gammapilot FTG 671, Руководство по эксплуатации

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Detector DG 17, DG 27 The Gammapilot FTG can also be connected to a DG 17/DG 27 Geiger-Müller counter.
In this counter each gamma quantum causes a cascade of ions which are registered by
the counter as a current pulse. The electronics process the pulses and pass a countra-
te-proportional frequency signal on to the FTG 671.
Four different Geiger-Müller counters are available, see Table 2.2. The detectors can be
fitted with a water jacket for use in hot surroundings. Similarly a flange or clamps are
available for mounting. The explosion protection is: DG 17, DG 27 - none
Ø65
BA082D09
Ions created by gamma rays move to
anode and cathode causing a current
to flow
Gas filled envelope with high voltage drop
Anode
Cathode
Fig. 2.6:
Function of the DG 17/27
Geiger-Müller counter
Detector types DG 17 DG 27
Number of counter tubes One Two
Dose rate range
(lateral mounting) 7
…
60 pA/kg =
1,2
…
8
µ
Sv/h (0,12
…
0,8 mR/h)
3,5
…
30 pA/kg=
0,6
…
4
µ
Sv/h (0,06
…
0,4 mR/h)
Dose rate range
(frontal mounting) 14
…
120 pA/kg =
2,4
…
16
µ
Sv/h (0,24
…
1,6 mR/h)
7
…
60 pA/kg
1,2
…
8
µ
Sv/h (0,12
…
0,8 mR/h)
Table 2.4:
Geiger-Müller counter
versions
86.
8
Position of detector
DG 17 DG 27
water jacket
in
out
ca. 140
ca. 280
200
20
Ø18
Ø220
DN 100 PN 16
Ø98
258
Ø
180
20
Ø1
8
Ø
220
8,4
119,6
Ø9
6
278
ca. 296
Ø
180
BA082D48
8,4
Fig. 2.7:
Dimensions in mm
Geiger-Müller counters
DG 17/27
DG 17 with mounting
flange
Gammapilot FTG 671 Chapter 2: Installation
16