Radiation to be detected :
X -ray & Gamma Radiation.
0.00 - 100.00 mR/hr
0 - 1000.0 µSv/hr
0 - 50000 CPM
0 - 2000 CPS
Range and Unit are configurable
Detector : Halogen quenched G. M. Tube. GM131E or Equivalent.
Energy Dependence : Within +/- 18% of true dose rate from 100 keV to 1.33 MeV gamma rays.
Accuracy : +/ - 10% with Cs-137
EHT : 400V to 700V DC adjustable (Typical 500V)
Display : Auto ranging direct reading, 6 digit 7 segment LED display & 16x2 LCD display. 6x7 LED display is interfaced using multiplexed display driver. 6x7 segment display is used for display of dose-rate and hardware status indication & 16x2 LCD for visualization of preset alarm and other parameters.
Display Resolution : 0.01mR/hr / 0.1 µSv/hr / 1 CPS / 1 CPM
Overload : Senses overload above 200% of full scale and upto 10R/h & indicates “OL” on display.
Over-range : Senses if the radiation field being measured has exceeded the measurement range of the instrument above 200% of the higher range and displays “OFl”
Recorder output : 4 to 20 mA, with 600 ohms load.
Time Constant : First reading on Power ON within 5 secs.
Normal (Slow) : 30 sec to 0.5 sec automatically varying inversely with the radiation level (Count rate).
Abrupt detection : Updates the current reading within 2 sec and returns to normal mode.
Calibration Accuracy : +/- 10% through out the range.
Instrument “ON” Indication : RED Neon indicating A.C. lamp
Alarm range : 0.1 - 99.9 mR/hr OR
1 - 999 µSv/hr
0 - 50000 CPM OR
1 - 2000 CPS
The alarm level setting can be set through front panel keypad or RS-485 Serial port using handheld configurator or PC provided with password protection. Front panel keypad is provided with DIP switch de-activation
Alarm Indication :
a) RED (LED) flashing large area window display
b) Loud audio tone (dual frequency tone)
Alarm annunciation scheme : As tabulated below
a) Acknowledgement switch for muting audio
b) Reset switch for resetting the Alarm indication and alarm relay.
c) Power ON/OFF switch (This is inside the cabinet) with Power ON indication
Instrument Fault indication:
a) EHT failure: Visual alarm with flashing RED LED indication & “EHT” message on display
b) Detector failure: Visual alarm with flashing red LED & “d-FL” message on display.
c) Microprocessor / microcontroller failure: Visual alarm with flashing green lamp.
d) Fault indications shall be cleared automatically if normal status is resumed.
a) The G. M. Detector is located external to the Monitor.
b) It is housed in a suitable, air-tight SS shell with built-in pre-amplifier to drive upto 50 mtrs long cable.
a) Vapor-tight, rugged & elegant.
b) The door is provided with lock and key arrangement
c) The enclosure is designed to qualify minimum industrial protection Class IP-54.
Mounting: Detector housing is mounted using clamps on top of the monitor. The monitor is wall mountable type. Brackets for the monitor & detector housing are supplied along with the equipment.
Remote /External Console :
a) 4 - 20 mA linear, proportional to full scale display output. Current output will be able to drive load of 600 ohms. (Output circuitry shall be able to drive 200 mtrs. of twisted pair of wires).
b) Two sets of potential free contacts of Alarm relay (Change over). Contact rating 3 Amp at 250 VAC. The relay gets energized on NORMAL condition and de-energized under ALARM condition.
c) Remote alarm acknowledgement and reset signals for the field instruments (Normally open contact).
d) Indication of instrument fault condition (detector, EHT and LV supplies), over range & overload conditions by up-scale 4-20 mA. (22.5 mA)
e) All these signals are terminated on a 17 pin I/O connector (Allied Connectors). The corresponding mating plug with 5 mtr cable is supplied with the monitor
f) RJ45 connector for Ethernet port
g) RS-485 serial port (optional). This is provided, on a pair of D-type connectors (male & female).
Computer Interface :
The monitor shall have a Ethernet 10/100 Mbps port for interfacing with a remote IBM PC-compatible computer. The features supported by Ethernet port are given below.
• The PC and the monitor shall operate in a host-slave configuration and the software protocol will be MODBUS/TCP.
• The PC as the host shall give commands and send queries. The monitor will carry out various functions in response to the queries.
• The firmware of the monitor shall be able to send the instrument data like instrument ID, instrument type, input range, display range, alarm settings, alarm status, current reading, diagnostic status of EHT/GM tube etc. to the Host PC on demand.
• The firmware shall be able to receive commands from Host PC and carry out the setting of different parameters like instrument ID, instrument type, input range, display range, alarm settings, Ack, Reset, instrument address etc.
RS485 (Optional) :
This monitor has a RS-485 Serial Communication port for interfacing with a PC. The PC and the monitor operate in a host-slave configuration in a multi-drop network through this interface. The PC, as the host will give commands and send queries. The monitor will carry the various functions as per the required information in response to the queries.
The firmware of the monitor sends the instrument data like Instrument ID, Instrument type, Input range, Display range, alarm settings, alarm status, current reading, diagnostic status of EHT/GM tube etc. to the Host PC on demand. The firmware receives commands from Host PC and carries out the setting of different parameters like Instrument ID, Instrument type, Input range, Display range, alarm settings, Ack, Reset, EHT setting, Instrument address etc. The configuration settings are password protected and the password is user defined.
The detailed specifications for the interface are as follows:-
Type : RS-485 Multi-drop Serial Communication Port, Half Duplex Bi-directional communication.
Character Format : ASCII
Protocol : Modbus/RTU
Bit Rate : User configurable to 9600 or 19200 bits per sec.
Address : User configurable from 0 to 255.
Connector : 9-pin D-type connectors (2 connectors connected in parallel for daisy chaining a number of instruments). The mating connectors with cover are supplied.
Self Diagnostics : The monitor has built-in self diagnostics. On being powered it performs tests to ensure that all components and sub-systems are functioning properly. It checks for the Power supply, High Voltage Supply, Detector and pulse processing electronics.
Input Power : 230VAC +/-10%, 50Hz, single phase supply. Power ON/OFF switch is provided with a neon indicator. Spike suppressor and line filter are also provided.
Environment : This instrument can withstand temperature upto 50o C and relative humidity upto 90% in radiation areas.
Environmental compliance : As per IS 9000 / ANSI N 42.17
The instrument enclosure and detector assembly are IP-54 compliant.. Electronic unit will withstand cumulative radiation dose of 10000 Rad. (30 years of operation).
Seismic qualification : Electronic unit, its wall mounting bracket, detector probe, wall mounting clamp and floor mounting stand are seismic qualified confirming to IEEE-344
EMI / EMC compliance : As per IEC 61000 / ANSI N42.17
Mechanical Enclosure :
Size : 357H x 380W x 140D,
Weight : 8.5kg approx