Technical Description. Ionisation Chambers

Transcription

1 Technical Description Ionisation Chambers

2 Manufacturer: IMS Messsysteme GmbH Dieselstraße Heiligenhaus Tel.: +49 (0) 2056 / Fax: +49 (0) 2056 / info@ims-gmbh.de (c) IMS Messsysteme GmbH. All rights reserved. This documentation is protected in all parts by copyright laws. Distribution and reproduction without the prior written authorisation of IMS Messsysteme GmbH are prohibited. All company and product names used in this documentation may be registered trademarks. 2/20 Vers.: HW_IK_0104_en

3 Contents 1 Application Description Types/ Order Text Types Order Text Technical Data Series KG Series KG Series KB Series KG Series KG Series KG Dimensional Drawings Connection of Ionisation Chambers Ionisation Chambers without RC Filter (High Voltage Filter) Ionisation Chambers with RC Filter (High Voltage Filter) General Information Storage and Transport Mounting Handling of Unusable Ionisation Chambers HW_IK_0104_en Vers.: /20

4 1 Application Ionisation chambers are used in radiometry as detectors to measure radioactive radiation and therefore belong to the most important components of IMS gauging systems in the field of radiometry (e.g. to measure thickness, profile and edge drop). Their output signal is a direct current proportional to the incident radiation. With their technical features, proven operational reliability and practically unlimited lifetimes, they satisfy all the necessary prerequisites for use at points of radiometric gauging systems exposed to radiation. 2 Description In principle the ionisation chamber is constructed like a cylinder or plate capacitor. The signal and voltage electrodes are housed in a closed tubular steel housing, which is filled with inert gas and has a beam entrance window on the front side. The voltage electrode is connected to the positive pole of the high-voltage power supply (generator of the operating voltage = chamber high voltage needed for the operation of ionisation chambers) and the signal electrode to the amplifier input. Special coax cables are used for these connections. Connected to the shielding of the coax cable to the signal electrode, the housing of the ionisation chamber is always connected to earth potential to shield against external parasitic induction. The incident radioactive radiation causes the gas to ionise. Under the influence of the electric field the negative electrons migrate to the positive voltage electrode and the ions to the signal electrode (measuring electrode). The ionisation chambers are operated in so-called saturation range, i.e. small changes in the operating voltage have practically no influence on the ionisation chamber current measurable at the signal electrode. The ionisation chambers come in various versions. The type of construction, gas and operating pressure as well as the thickness and material of the beam entrance window all determine the "measuring" characteristics of the chambers and simultaneously constitute their main distinguishing features. The elementary distinguishing features are summarised in tabular form in the chapter "Technical Data". Ionisation chambers of the same type of construction form a series. The choice of ionisation chamber is application-specific and depends primarily on the type of radiation, which is determined by the particular task in question. If the task allows different versions to be used, other criteria e.g. the mounting situation can influence the choice. 4/20 Vers.: HW_IK_0104_en

5 3 Types/ Order Text 3.1 Types Type Article No. Main Field of Application for Measurement of Series KG 60 KG 60 / 50 (KG 60 / AM) γ - radiation (Am 241) / X-radiation KG 60 / γ - radiation (Am 241) / X-radiation KG 60 / γ - radiation (Am 241) / X-radiation KG 60 / X-radiation KG 60 / 60 (KG 60 / CS 12) γ - radiation (Cs 137) KG 60 / 61 (KG 60 / CS 18) γ - radiation (Cs 137) Series KG 126 KG 126 / 50 (KG 126 / AM) γ - radiation (Am 241) / X-radiation KG 126 / 61 (KG 126 / CS - KR) γ - radiation (Cs 137) KG 126 / 62 (KG 126 / CS - XE) γ - radiation (Cs 137) Series KB 100 KB 100 / 10 (KB 100 / PM) β - radiation (Pm 147) KB 100 / 20 (KB 100 / KR) β - radiation (Kr 85) KB 100 / 30 (KB 100 / SR) β - radiation (Sr 90) Series KG 100 KG 100 / 40 (KG 100 / CM) γ - radiation (Cm 244) / X-radiation KG 100 / 41 (KG 100 / CM - XE) γ - radiation (Cm 244) / X-radiation KG 100 / 50 (KG 100 / AM) γ - radiation (Am 241) / X-radiation Series KG 90 KG 90 / 10 (KG 90 / FE) Secondary radiation KG 90 / 20 (KG 90 / PM) Secondary radiation / X-radiation KG 90 / 30 (KG 90 / KR) Secondary radiation / X-radiation Series KG 20 KG 20 / X-radiation 10/11/12 KG 20 / X-radiation 20/21/22 KG 20 / Secondary radiation / X-radiation KG 20 / Secondary radiation / X-radiation KG 20 / Secondary radiation / X-radiation KG 20 / Secondary radiation / X-radiation Printed in italics = original type designation Article no. = Drawing no. γ - radiation / β - radiation / X-radiation: Measurement - transmission technique Secondary radiation (backscatter radiation, fluorescent radiation): Measurement - backscatter technique HW_IK_0104_en Vers.: /20

6 3.2 Order Text The order text comprises the type designation and the article number. 4 Technical Data 4.1 Series KG 60 Type KG 60 / 50 KG 60 / 51 KG 60 / 52 Original type designation (KG 60 / AM) (KG 60 / AM - KR) Article No. (Drawing No.) Characteristic Data Chamber volume (gas volume) ca. [l] Radiosensitive volume ca. [l] Gas Xenon Krypton Xenon Gas pressure [Pa] 7,5x10 5 3,5x ,5x10 5 Window material Stainless steel Stainless steel Stainless steel Window thickness [µm] Window with protective grating No No No Internal capacitance - Signal electrode [pf] 30 - Voltage electrode [pf] 74 Operating voltage (chamber high voltage) - Maximum value U Hmax [V] 2000 RC filter in connection head No Connection cable (standard length) [m] 6 Weight (without /with connection cable) [kg] 0.9 / 1.3 General Data Type of construction See dimensional drawing chapter 5 Insulation resistance [Ω] > System of housing protection IP 64 (EN 60259) Climatic conditions - Ambient temperature [ C] Transport and storage temperature [ C] Location of the sensitive chamber volume: see shading respectively hatching in dimensional drawing Measured between the electrode connections in the chamber and housing Connection cable for operating voltage (chamber high voltage) marked red 6/20 Vers.: HW_IK_0104_en

7 Series KG 60 (continuation) Type KG 60 / 53 KG 60 / 60 KG 60 / 61 Original type designation (KG 60 / CS - 12) (KG 60 / CS - 18) Article No. (Drawing No.) Characteristic Data Chamber volume (gas volume) ca. [l] 0,3 0,3 0,5 Radiosensitive volume ca. [l] 0,2 0,2 0,3 Gas Xenon Xenon Xenon Gas pressure [Pa] 14.5x x x10 5 Window material Stainless steel Stainless steel Stainless steel Window thickness [µm] Window with protective grating No No No Internal capacitance - Signal electrode [pf] Voltage electrode [pf] Operating voltage (chamber high voltage) - Maximum value U Hmax [V] 2000 RC filter in connection head No Connection cable (standard length) [m] 6 Weight (without / with connection cable) [kg] 0,9 / 1,3 1,1 / 1,6 1,6 / 2 General Data Type of construction See dimensional drawing chapter 5 Insulation resistance [Ω] > System of housing protection IP 64 (EN 60259) Climatic conditions - Ambient temperature [ C] Transport and storage temperature [ C] Location of the sensitive chamber volume: see shading respectively hatching in dimensional drawing Measured between the electrode connections in the chamber and housing Connection cable for operating voltage (chamber high voltage) marked red HW_IK_0104_en Vers.: /20

8 4.2 Series KG 126 Type KG 126 / 50 KG126 / 61 KG 126 / 62 Original type designation (KG 126 / AM) (KG 126 / CS - KR) (KG 126 / CS - XE) Article No. (Drawing No.) Characteristic Data Chamber volume (gas volume) ca. [l] Radiosensitive volume ca. [l] Gas Xenon Krypton Xenon Gas pressure [Pa] 3.5x x x10 5 Window material Stainless steel Stainless steel Stainless steel Window thickness [µm] Window with protective grating No No No Internal capacitance - Signal electrode [pf] 75 - Voltage electrode [pf] 160 Operating voltage (chamber high voltage) - Maximum value U Hmax [V] 2000 RC filter in connection head 470kΩ/ 10nF/4000V Connection cable No Weight [kg] General Data Type of construction See dimensional drawing chapter 5 Insulation resistance [Ω] > System of housing protection IP 64 (EN 60259) Climatic conditions - Ambient temperature [ C] Transport and storage temperature [ C] Location of the sensitive chamber volume: see shading respectively hatching in dimensional drawing Measured between the electrode connections in the chamber and housing The coax cable (article no ) must be used as connection cable for operating voltage and measuring signal 8/20 Vers.: HW_IK_0104_en

9 4.3 Series KB 100 Type KB 100 / 10 KB 100 / 20 KB 100 / 30 Original type designation (KB 100 / PM) (KB 100 / KR) (KB 100 / SR) Article No. (Drawing No.) Characteristic Data Chamber volume (gas volume) ca. [l] Radiosensitive volume ca. [l] Gas Argon Krypton Xenon Gas pressure [Pa] 1.4x10 5 3x10 5 5x10 5 Window material Titanium Titanium Titanium Window thickness [µm] Window with protective grating Yes Yes Yes Internal capacitance - Signal electrode [pf] Voltage electrode [pf] 560 Operating voltage (chamber high voltage) - Maximum value U Hmax [V] 1000 RC filter in connection head No Connection cable No Weight [kg] 4 General Data Type of construction See dimensional drawing chapter 5 Insulation resistance [Ω] > System of housing protection IP 64 (EN 60259) Climatic conditions - Ambient temperature [ C] Transport and storage temperature [ C] Location of the sensitive chamber volume: see shading respectively hatching in dimensional drawing Measured between the electrode connections in the chamber and housing The coax cable (article no ) must be used as connection cable for operating voltage and measuring signal HW_IK_0104_en Vers.: /20

10 4.4 Series KG 100 Type KG 100 / 40 KG 100 / 41 KG 100 / 50 Original type designation (KG 100 / CM) (KG 100 / CM - (KG 100 / AM) XE) Article No. (Drawing No.) Characteristic Data Chamber volume (gas volume) ca. [l] Radiosensitive volume ca. [l] Gas Krypton Xenon Xenon Gas pressure [Pa] 1.6x10 5 2x10 5 6x10 5 Window material Titanium Titanium Titanium Window thickness [µm] Window with protective grating No No No Internal capacitance - Signal electrode [pf] Voltage electrode [pf] 560 Operating voltage (chamber high voltage) - Maximum value U Hmax [V] 1000 RC filter in connection head 4,7 MΩ/ 10nF/4000V Connection cable No Weight [kg] 4 General Data Type of construction See dimensional drawing chapter 5 Insulation resistance [Ω] > System of housing protection IP 64 (EN 60259) Climatic conditions - Ambient temperature [ C] Transport and storage temperature [ C] Location of the sensitive chamber volume: see shading respectively hatching in dimensional drawing Measured between the electrode connections in the chamber and housing The coax cable (article no ) must be used as connection cable for operating voltage and measuring signal 10/20 Vers.: HW_IK_0104_en

11 4.5 Series KG 90 Type KG 90 / 10 KG 90 / 20 KG 90 / 30 Original type designation (KG 90 / FE) (KG 90 / PM) (KG 90 / KR) Article No. (Drawing No.) Characteristic Data Chamber volume (gas volume) ca. [l] Radiosensitive volume ca. [l] Gas Argon Argon Krypton Gas pressure [Pa] 1.1x x x10 5 Window material Beryllium Titanium Titanium Window thickness [µm] Window with protective grating No No No Internal capacitance - Signal electrode [pf] 20 - Voltage electrode [pf] 60 Operating voltage (chamber high voltage) - Maximum value U Hmax [V] 1000 RC filter in connection head No Connection cable No Weight [kg] 2.7 General Data Type of construction See dimensional drawing chapter 5 Insulation resistance [Ω] > System of housing protection IP 64 (EN 60259) Climatic conditions - Ambient temperature [ C] Transport and storage temperature [ C] Location of the sensitive chamber volume: see shading respectively hatching in dimensional drawing Measured between the electrode connections in the chamber and housing The coax cable (article no ) must be used as connection cable for operating voltage and measuring signal HW_IK_0104_en Vers.: /20

12 4.6 Series KG 20 Type KG 20 / 10 KG 20 / 20 KG 20 / 30 Design 0, 1, 2 0, 1, 2 Article No. (Drawing No.) /11/ /21/ Characteristic Data Chamber volume (gas volume) ca. [l] Radiosensitive volume ca. [l] Gas Xenon Krypton Krypton Gas pressure [Pa] 6.5x x x10 5 Window material Stainless steel Stainless steel Titanium Window thickness [µm] Window with protective grating No No No Internal capacitance - Signal electrode [pf] 25 - Voltage electrode [pf] 55 Operating voltage (chamber high voltage) - Maximum value U Hmax [V] 1600 RC filter in connection head No Connection cable No Weight (design 0 respectively 1 / 2) [kg] 0.7 / General Data Type of construction See dimensional drawing chapter 5 Insulation resistance [Ω] > System of housing protection IP 64 (EN 60259) Climatic conditions - Ambient temperature [ C] Transport and storage temperature [ C] Location of the sensitive chamber volume: see shading respectively hatching in dimensional drawing Measured between the electrode connections in the chamber and housing The double coax cable (article no ) must be used as connection cable Differences relating to the connecting boxes only are limited to the types KG 20 / 10 and KG 20 / 20 12/20 Vers.: HW_IK_0104_en

13 Series KG 20 (continuation) Type KG 20 / 40 KG 20 / 50 KG 20 / 60 Article No. (Drawing No.) Characteristic Data Chamber volume (gas volume) ca. [l] Radiosensitive volume ca. [l] Gas Argon Argon Argon Gas pressure [Pa] 2x x x10 5 Window material Titanium Titanium Beryllium Window thickness [µm] Window with protective grating No No No Internal capacitance - Signal electrode [pf] 25 - Voltage electrode [pf] 55 Operating voltage (chamber high voltage) - Maximum value U Hmax [V] 1600 RC filter in connection head No Connection cable No Weight (design 0 respectively 1 / 2) [kg] 0.9 General Data Type of construction See dimensional drawing chapter 5 Insulation resistance [Ω] > System of housing protection IP 64 (EN 60259) Climatic conditions - Ambient temperature [ C] Transport and storage temperature [ C] Location of the sensitive chamber volume: see shading respectively hatching in dimensional drawing Measured between the electrode connections in the chamber and housing The double coax cable (article no ) must be used as connection cable HW_IK_0104_en Vers.: /20

14 5 Dimensional Drawings KG 60 KB 100 and KG ,5 L L3 L E L L L2 L L1 Dim. L [mm] L1 [mm] L2 [mm] LE [mm] Dim. L1 [mm] L2 [mm] L3 [mm] L4 [mm] KG 60 / 50 ca KB 100 / 10 16, ,5 KG 60 / 51 ca KB 100 / 20 16, ,5 KG 60 / 52 ca ca KB 100 / 30 20,2 104,5 151,5 11 KG 60 / 53 ca ca KG 60 / 60 ca KG 100 / 40 16, ,5 KG 60 / 61 ca KG 100 / 41 16, ,5 KG 100 / 50 20,2 104,5 151, /20 Vers.: HW_IK_0104_en

15 KG 126 / 50 KG 126 / 61 and KG 126 / KG HW_IK_0104_en Vers.: /20

16 KG 20 / 10 and KG 20 / 20, each design 0 16/20 Vers.: HW_IK_0104_en

17 KG 20 / 10 and KG 20 / 20, each design 1 KG 20 / 10 and KG 20 / 20, each design 2 HW_IK_0104_en Vers.: /20

18 KG 20 / 30 / 40 / 50 / 60 18/20 Vers.: HW_IK_0104_en

19 6 Connection of Ionisation Chambers 6.1 Ionisation Chambers without RC Filter (High Voltage Filter) Only KG 20 U S 1 S U gr sw 1 S : Signalelektrode / Signal electrode U : Spannungselektrode / Voltage electrode 1 : Schirm / Shielding Rote Markierung Red marking /6 6.2 Ionisation Chambers with RC Filter (High Voltage Filter) Only the connection rooms of the ionisation chambers KG 126 and KG 100 are equipped with RC filters (high voltage filters). The values for R and C are to be found in the technical data (4.2 and 4.4.). U R C 1 S S : Signalelektrode / Signal electrode U : Spannungselektrode / Voltage electrode 1 : Schirm / Shielding Rote Markierung Red marking /6 HW_IK_0104_en Vers.: /20

20 7 General Information See the "Assembly Instructions - Part 1" for detailed information on storage, transport and assembly 7.1 Storage and Transport Some ionisation chambers are equipped with a protective cover to protect the beam entrance window during storage and transport. It is recommended that this protective cover only be removed after mounting of the ionisation chamber. 7.2 Mounting Low-noise, high-impedance coax cables are used as connection cables for the measuring signal and operating voltage (chamber high voltage). They can be bought - as special accessories - under the article numbers given in the table below. Article No. Article Designation Outside Remarks [mm] Coax cable Double coax cable 7.2 Coax 1: black Coax 2: grey A coax cable each is needed for the measuring signal and operating voltage (chamber high voltage). The handling instructions for coax cables in the operating manual should be followed to avoid losses in insulation. For technical measuring reasons, the connections S (signal electrode) and U (operating voltage) in the connection head of the ionisation chambers may not be interchanged. In the case of ionisation chambers delivered ex works with connection cables the coax cable for the operating voltage is marked with a red marking. In double coax cables the - inner - grey coax conductor carries the operating voltage. After mounting the cables the connection-room cover and cable entries must be closed carefully to guarantee permanently the necessary insulation resistance of > 10¹² Ω. 7.3 Handling of Unusable Ionisation Chambers To counteract potential explosion hazards, ionisation chambers that have become unusable should be depressurised by opening the pump connection in the connection room. Special measures must be taken when disposing of ionisation chambers with a beryllium window, e.g. special protective measures. See the chapter "Hazardous Materials" in the document "Safety Information Measuring System" for further information. 20/20 Vers.: HW_IK_0104_en