| Line 20 was replaced by lines 20-21 |
| - * helium level meter and probe are described in separate manuals. |
| + * helium level meter and probe |
| + are described in separate manuals. |
| Lines 40-46 were replaced by lines 41-47 |
| - * Transfer tube entry port |
| - * Magnet current lead coaxial terminal (two sets) |
| - * Helium level probe |
| - * Electrical access to the magnet switch heaters and temperature sensors |
| - * Helium reservoir exhaust ports (connected to each other with a recovery manifold) VTI sample space needle valve and electrical access to heater and temp sensor (for clearing blockages) |
| - * Lambda point refrigerator needle valve and pumping line |
| - * Electrical access to VTI sample space heat exchanger temp sensor and heater Please refer to the wiring general arrangement drawing AGO 1351. |
| + * Transfer tube entry port |
| + * Magnet current lead coaxial terminal (two sets) |
| + * Helium level probe |
| + * Electrical access to the magnet switch heaters and temperature sensors |
| + * Helium reservoir exhaust ports (connected to each other with a recovery manifold) VTI sample space needle valve and electrical access to heater and temp sensor (for clearing blockages) |
| + * Lambda point refrigerator needle valve and pumping line |
| + * Electrical access to VTI sample space heat exchanger temp sensor and heater Please refer to the wiring general arrangement drawing AGO 1351. |
| Line 88 was replaced by line 89 |
| - a) 1. 5K < T < 4.2K |
| + a) 1. 5K - 4.2K |
| Line 92 was replaced by line 93 |
| - b) 4.2K < T < 300K mode |
| + b) 4.2K - 300K mode |
| Line 121 was replaced by line 122 |
| - !2.1.1 Magnet Service Necks |
| + ''2.1.1 Magnet Service Necks'' |
| Line 164 was replaced by line 165 |
| - ''Important'' |
| + ''Important:'' |
| Line 166 was replaced by lines 167-169 |
| - Before disassembly all cryogen's should be removed from the cryostat and all parts of the system should be allowed to warm to room temperature. |
| + * Before disassembly all cryogen's should be removed from the cryostat and all parts of the system should be allowed to warm to room temperature. |
| + * Take care not to trap cryogen's in closed off volume - high pressures will result causing possible damage to the equipment. |
| + * Particular care should be taken with regard to the VTI and lambda point refrigerator. Take care not to isolate cold gas in lines that are closed off between shut-off valves, far better review operating procedures so that one of the valves can be omitted from the gas handling circuit. |
| Removed line 168 |
| - Take care not to trap cryogen's in closed off volume - high pressures will result causing possible damage to the equipment. |
| Removed lines 170-172 |
| - Particular care should be taken with regard to the VTI and lambda point refrigerator. Take care not to isolate cold gas in lines that are closed off between shut-off valves, far better review operating procedures so that one of the valves can be omitted from the gas handling circuit. |
| - |
| - |
| Lines 192-202 were replaced by lines 191-197 |
| - 1. When replacing assemblies, take care not to damage any electrical wiring. Check wiring at each stage of assembly for continuity at short circuits. One area where this is particularly important is the fitting of the VTI inner parts into the bore of the magnet. |
| - |
| - 2. Make certain that all flanges are replaced with the same relative orientation they had when removed. Alphabet characters have been punched on mating flanges and these should be placed together for correct orientation. |
| - |
| - 3. Ensure that all O-rings are clean and lightly greased with vacuum grease. |
| - |
| - 4. Avoid grease and finger marks on any superinsulated surfaces. Clean with a degreasing fluid if necessary. |
| - |
| - 5. When remaking indium seals use new or re-extruded 1 mm diameter indium wire. Ensure that all mating surfaces are clean and dry. Wrap a single turn around the male half of the jointing flanges; the ends of the wire should cross each other. Assembled the joint and fit the bolts. Tighten the bolts evenly and gradually, in a methodical diagonal order until the indium is fully compressed. Check that the joint is leak tight before proceeding further. |
| - |
| - 6. Make sure that the radial spacing on the VTI and its radiation shield are set so that they cannot touch each other or the helium reservoir bore tube. Also check the capillary tube for touches. |
| + # When replacing assemblies, take care not to damage any electrical wiring. Check wiring at each stage of assembly for continuity at short circuits. One area where this is particularly important is the fitting of the VTI inner parts into the bore of the magnet. |
| + # Make certain that all flanges are replaced with the same relative orientation they had when removed. Alphabet characters have been punched on mating flanges and these should be placed together for correct orientation.\\ \\ |
| + # Ensure that all O-rings are clean and lightly greased with vacuum grease.\\ \\ |
| + # Avoid grease and finger marks on any superinsulated surfaces. Clean with a degreasing fluid if necessary.\\ \\ |
| + # When remaking indium seals use new or re-extruded 1 mm diameter indium wire. Ensure that all mating surfaces are clean and dry. Wrap a single turn around the male half of the jointing flanges; the ends of the wire should cross each other. Assembled the joint and fit the bolts. Tighten the bolts evenly and gradually, in a methodical diagonal order until the indium is fully compressed. Check that the joint is leak tight before proceeding further.\\ \\ |
| + # Make sure that the radial spacing on the VTI and its radiation shield are set so that they cannot touch each other or the helium reservoir bore tube. Also check the capillary tube for touches.\\ \\ |
| + # If the magnet has been removed take care to solder the leads from the magnet to their correct cryostat current leads (check continuity and identity using a multimeter). Insulate the soldered joints against high voltage. Connect all electrical connectors, and connect the lower fill/blow-out tube to the upper using the compression union. All these connections are made at the magnet indium seal level. |
| Removed line 204 |
| - 7. If the magnet has been removed take care to solder the leads from the magnet to their correct cryostat current leads (check continuity and identity using a multimeter). Insulate the soldered joints against high voltage. Connect all electrical connectors, and connect the lower fill/blow-out tube to the upper using the compression union. All these connections are made at the magnet indium seal level. |
| Removed line 206 |
| - |
| Lines 213-217 were replaced by lines 206-207 |
| - a) |
| - Connect the valve on the cryostat top flange to the pumping equipment. Using the rotary pump, evacuate the cryostat until the pressure is less than 1 torr, then admit an atmosphere of DRY nitrogen gas and pump out again. Repeat several times, then finally pump to less that 0.005 torr |
| - |
| - b) |
| - Switch over to the diffusion pump and evacuate the cryostat to less than 5 x 10-5 torr Continue pumping at least overnight, to ensure the removal of residual gases trapped in the superinsulation. |
| + # Connect the valve on the cryostat top flange to the pumping equipment. Using the rotary pump, evacuate the cryostat until the pressure is less than 1 torr, then admit an atmosphere of DRY nitrogen gas and pump out again. Repeat several times, then finally pump to less that 0.005 torr. |
| + # Switch over to the diffusion pump and evacuate the cryostat to less than 5 x 10-5 torr. Continue pumping at least overnight, to ensure the removal of residual gases trapped in the superinsulation. |
| Line 224 was replaced by line 214 |
| - !4.2.1 Filling the liquid nitrogen container |
| + ''4.2.1 Filling the liquid nitrogen container'' |
| Lines 236-237 were replaced by lines 226-227 |
| - Important: |
| - The nitrogen vent ports should be periodically checked for blockages and cleared when necessary. Ice blockage can occur on the unprotected vents due to air being sucked in through the vents when the LN2 is sub cooled by a relatively high flow of cold helium gas during helium transfer or a quench. |
| + ''Important:'' |
| + * The nitrogen vent ports should be periodically checked for blockages and cleared when necessary. Ice blockage can occur on the unprotected vents due to air being sucked in through the vents when the LN2 is sub cooled by a relatively high flow of cold helium gas during helium transfer or a quench. |
| Line 240 was replaced by line 230 |
| - !4.2.2 Precooling the Magnet |
| + ''4.2.2 Precooling the Magnet'' |
| Line 244 was replaced by line 234 |
| - Control the flow of LN2 to the helium tank, to slowly precool and thereby protect the magnet, by connecting a restriction to the cryostat exhaust line (e.g. the one way valve provided or 12 ins. of 0.25 ins. bore tube) and by transferring the LN2 at an over pressure of approximately 260 torr |
| + Control the flow of LN2 to the helium tank, to slowly precool and thereby protect the magnet, by connecting a restriction to the cryostat exhaust line (e.g. the one way valve provided or 12 ins. of 0.25 ins. bore tube) and by transferring the LN2 at an over pressure of approximately 260 torr |
| Line 253 was replaced by line 243 |
| - !4.2.3 Initial filling with liquid helium4 |
| + ''4.2.3 Initial filling with liquid helium4'' |
| Line 269 was replaced by line 259 |
| - !4.2.4 Refilling with liquid helium |
| + ''4.2.4 Refilling with liquid helium'' |
| Lines 273-277 were replaced by lines 263-265 |
| - a) Insert one leg of the transfer tube into the storage vessel, but leave the other one outside of the cryostat. Pressurize the transport dewar in the normal way, as if transferring helium. After about a minute liquid will issue from the transfer tube, indicated by a blue tongue of vapor. (Prior to this a white vapor plume will have been seen for about 20 seconds). |
| - |
| - b) Quickly release the pressure in the transport dewar and insert the open end of the transfer tube into the cryostat. |
| - |
| - c) Lower the transfer tube until it reaches the bottom of the services neck. DO NOT push the transfer tube into the socket on top of the magnet. Transfer liquid helium in the usual way.If the helium level has fallen below 5% and the magnet is still energised there are two courses of action open: |
| + # Insert one leg of the transfer tube into the storage vessel, but leave the other one outside of the cryostat. Pressurize the transport dewar in the normal way, as if transferring helium. After about a minute liquid will issue from the transfer tube, indicated by a blue tongue of vapor. (Prior to this a white vapor plume will have been seen for about 20 seconds). |
| + # Quickly release the pressure in the transport dewar and insert the open end of the transfer tube into the cryostat. |
| + # Lower the transfer tube until it reaches the bottom of the services neck. DO NOT push the transfer tube into the socket on top of the magnet. Transfer liquid helium in the usual way. If the helium level has fallen below 5% and the magnet is still energised there are two courses of action open: |
| Line 279 was replaced by line 267 |
| - (i) If the level is below 0% or if the user is not certain that a careful transfer can be done - DE-ENERGISE THE MAGNET - refill and then re-energise the magnet. |
| + (i) If the level is below 0% or if the user is not certain that a careful transfer can be done - DE-ENERGISE THE MAGNET - refill and then re-energise the magnet. |
| Line 281 was replaced by line 269 |
| - (ii) Refill the dewar, but be careful as the siphon is introduced and as the transfer starts. |
| + (ii) Refill the dewar, but be careful as the siphon is introduced and as the transfer starts. |
| Lines 284-285 were replaced by lines 272-273 |
| - Important: |
| - Beware of the stray magnetic field when bringing magnetic objects close to the system with the magnet energised. |
| + ''Important:'' |
| + * Beware of the stray magnetic field when bringing magnetic objects close to the system with the magnet energised. |
| Lines 291-299 were replaced by line 279 |
| - Important: |
| - |
| - Before initial use, and if the system has not been used for some time the following measurements should be made, and compared with the quoted values. |
| - |
| - 1. |
| - Magnet resistance |
| - |
| - 2. |
| - Magnet to cryostat isolation |
| + ''Important:'' |
| Lines 301-302 were replaced by lines 281-285 |
| - 3. |
| - Resistances of the heaters for each switch |
| + * Before initial use, and if the system has not been used for some time the following measurements should be made, and compared with the quoted values. |
| + ** Magnet resistance |
| + ** Magnet to cryostat isolation |
| + ** Resistances of the heaters for each switch |
| + ** Isolation of the heaters for each switch |
| Removed lines 304-306 |
| - 4. |
| - Isolation of the heaters for each switch |
| - |
| Lines 309-328 were replaced by lines 289-296 |
| - 1. |
| - Before connecting the PS120-10 to the electricity supply, connect the magnet current leads and the persistent mode switch heater leads to the terminals inside the rear cover of the power supply. |
| - |
| - 2. |
| - Connect the leads to the relevant cryostat magnet terminals (depending on the mode of operation required) and to the switch heater ten pin seal. Check for electrical isolation from the cryostat. Switch on the magnet power supply. |
| - |
| - 3. |
| - The power supply will initialize by displaying, "PASS", then 0.00 |
| - |
| - 4. |
| - Select the power supply output to be displayed in amps. Set the current to which the magnet is to be energized by pressing the RAISE and LOWER buttons on the ADJUST panel while depressing the SET POINT button on the DISPLAY panel. Set the rate of change in a similar way by pressing RAISE and LOWER while depressing the SET RATE button. Please consult Section 5 of this manual for advised energisation limits. The SET RATE can be changed while the magnet is being energized so the SET POINT can be the value desired ultimately. |
| - |
| - 5. |
| - The magnet is equipped with two persistent mode switches in series, so press the HEATER ON button on the SWITCH HEATER panel. The button should be held down for about five seconds until the indicator light remains on when the button is released. |
| - |
| - 6. |
| - The magnet energisation can now be started by pressing the SET POINT button on the SWEEP CONTROL panel. The current or field will be seen to increase on the digital display and the output voltage will have been seen to kick over to the voltage needed to overcome the magnet impedance on the analogue meter. |
| - |
| - 7. |
| - When the set point has been reached, the switch heater can be turned off by pressing the HEATER ON button. After waiting about ten seconds for the switch to become superconducting, press the ZERO button on the SWEEP CONTROL panel. The current in the magnet leads will decrease to zero leaving the magnet, still energized, in persistent mode. The rate at which the leads alone can be swept is faster than the magnet and leads, this is automatically taken into account in the power supply software. |
| + # Before connecting the PS120-10 to the electricity supply, connect the magnet current leads and the persistent mode switch heater leads to the terminals inside the rear cover of the power supply. |
| + # Connect the leads to the relevant cryostat magnet terminals (depending on the mode of operation required) and to the switch heater ten pin seal. Check for electrical isolation from the cryostat. Switch on the magnet power supply. |
| + # The power supply will initialize by displaying, "PASS", then 0.00 |
| + # Select the power supply output to be displayed in amps. Set the current to which the magnet is to be energized by pressing the RAISE and LOWER buttons on the ADJUST panel while depressing the SET POINT button on the DISPLAY panel. Set the rate of change in a similar way by pressing RAISE and LOWER while depressing the SET RATE button. Please consult Section 5 of this manual for advised energisation limits. The SET RATE can be changed while the magnet is being energized so the SET POINT can be the value desired ultimately. |
| + # The magnet is equipped with two persistent mode switches in series, so press the HEATER ON button on the SWITCH HEATER panel. The button should be held down for about five seconds until the indicator light remains on when the button is released. |
| + # The magnet energisation can now be started by pressing the SET POINT button on the SWEEP CONTROL panel. The current or field will be seen to increase on the digital display and the output voltage will have been seen to kick over to the voltage needed to overcome the magnet impedance on the analogue meter. |
| + # When the set point has been reached, the switch heater can be turned off by pressing the HEATER ON button. After waiting about ten seconds for the switch to become superconducting, press the ZERO button on the SWEEP CONTROL panel. The current in the magnet leads will decrease to zero leaving the magnet, still energized, in persistent mode. The rate at which the leads alone can be swept is faster than the magnet and leads, this is automatically taken into account in the power supply software. |
| + # The magnet can be taken out of persistent mode by using the following procedure: |
| Removed lines 330-331 |
| - 8. |
| - The magnet can be taken out of persistent mode by using the following procedure: |
| Removed line 333 |
| - |
| Lines 340-341 were replaced by lines 305-306 |
| - Important: |
| - When operating the Lambda point refrigerator, boil off from the main helium reservoir will decrease and may reach negligible proportions. It is important therefore that precautions are taken to ensure that there is no chance of the cryostat 'sucking back', thereby introducing contaminants into the helium. It is recommended that the system is linked as in the figure overleaf, with the Lambda fridge pump exhaust pump connected to the main helium exhaust. The oil mist filter prevents possible contaminants entering the cryostat. Also ensure that there is sufficient liquid helium in main reservoir to achieve and maintain low temperature operation of the magnet. |
| + ''Important:'' |
| + * When operating the Lambda point refrigerator, boil off from the main helium reservoir will decrease and may reach negligible proportions. It is important therefore that precautions are taken to ensure that there is no chance of the cryostat 'sucking back', thereby introducing contaminants into the helium. It is recommended that the system is linked as in the figure overleaf, with the Lambda fridge pump exhaust pump connected to the main helium exhaust. The oil mist filter prevents possible contaminants entering the cryostat. Also ensure that there is sufficient liquid helium in main reservoir to achieve and maintain low temperature operation of the magnet. |
| Lines 352-353 were replaced by line 317 |
| - Changing the samples |
| - |
| + ''Changing the samples'' |
| Lines 355-360 were replaced by lines 319-325 |
| - a) Warm insert to approximately 300K. |
| - b) Place gas filled bladder on sample space exchange gas port and open the valve to ensure an over pressure of helium in the sample space. |
| - c) Remove sample holder. |
| - d) Immediately seal sample space with baffle set provided. |
| - e) To replace sample holder, follow the same procedure, noting that it |
| - may be necessary to turn the sample holder as it enter the sample space |
| + # Warm insert to approximately 300K. |
| + # Place gas filled bladder on sample space exchange gas port and open the |
| + valve to ensure an over pressure of helium in the sample space. |
| + # Remove sample holder. |
| + # Immediately seal sample space with baffle set provided. |
| + # To replace sample holder, follow the same procedure, noting that it |
| + may be necessary to turn the sample holder as it enter the sample space |
| Line 363 was replaced by line 328 |
| - Operating above 4.2K |
| + ''Operating above 4.2K'' |
| Line 367 was replaced by line 332 |
| - a) Gravity Feed. |
| + ''a) Gravity Feed'' |
| Lines 371-373 were replaced by lines 336-339 |
| - i) Connect the insert exhaust port to the helium vent / recovery position. |
| - |
| - ii) Open the needle valve to give the required flow and cooling power. |
| + # Connect the insert exhaust port to the helium vent / recovery position. |
| + # Open the needle valve to give the required flow and cooling power. |
| + # Once the required temperature has been attained, restrict the flow until the temperature settles at a value just below that required, or continues to drift slowly downwards. |
| + # Set the required temperature on the temperature controller and use the heater to bring the insert to the required value. |
| Removed line 375 |
| - iii) Once the required temperature has been attained, restrict the flow until the temperature settles at a value just below that required, or continues to drift slowly downwards. |
| Line 377 was replaced by line 342 |
| - iv) Set the required temperature on the temperature controller and use the heater to bring the insert to the required value. |
| + ''b) Pumped Feed'' |
| At line 378 added 4 lines. |
| + # Connect the insert exhaust to a suitable pump (approximately 450 1/min). |
| + # Initially evacuate with the needle valve closed. |
| + # Open the needle valve to give the required cooling power. |
| + # Operation and control are as for (a) above. |
| Removed line 380 |
| - b) Pumped Feed |
| Lines 382-385 were replaced by line 350 |
| - a) Connect the insert exhaust to a suitable pump (approximately 450 1/min). |
| - b) Initially evacuate with the needle valve closed. |
| - c) Open the needle valve to give the required cooling power. |
| - d) Operation and control are as for (a) above. |
| + ''Operation below 4.2K'' |
| At line 386 added 1 line. |
| + Temperatures below 4.2K are achieved by pumping against the needle valve, thereby reducing the vapor pressure and therefore the temperature of the helium. Operation can be either continuous or single shot, the latter providing the ultimate base temperature. |
| Removed lines 388-391 |
| - Operation below 4.2K |
| - |
| - Temperatures below 4.2K are achieved by pumping against the needle valve, thereby reducing the vapor pressure and therefore the temperature of the helium. Operation can be either continuous or single shot, the latter providing the ultimate base temperature. |
| - |
| Line 395 was replaced by line 357 |
| - (i) Continuous operation |
| + ''a) Continuous operation'' |
| Line 397 was replaced by line 359 |
| - Operation is basically as for operation above 4.2K, except that the needle valve is merely cracked open with the pump running. Temperature control is achieved by controlling the pumping pressure via the manostat, the operation of which is described in its own manual. This method will provide a base temperature of 2 - 2.5K, depending on the heat input from the sample support rod. |
| + Operation is basically as for operation above 4.2K, except that the needle valve is merely cracked open with the pump running. Temperature control is achieved by controlling the pumping pressure via the manostat, the operation of which is described in its own manual. This method will provide a base temperature of 2 - 2.5K, depending on the heat input from the sample support rod. |
| Line 400 was replaced by line 362 |
| - (ii) Single shot operation |
| + ''b) Single shot operation'' |
| Line 402 was replaced by line 364 |
| - This mode involves filling the insert pumping pot with helium, closing the needle valve, and then pumping on the helium to reduce its pressure and therefore temperature. It allows the ultimate base temperature to be reached, but obviously the size of the pot restricts the operating time before the helium is exhausted. |
| + This mode involves filling the insert pumping pot with helium, closing the needle valve, and then pumping on the helium to reduce its pressure and therefore temperature. It allows the ultimate base temperature to be reached, but obviously the size of the pot restricts the operating time before the helium is exhausted. |
| Line 408 was replaced by line 370 |
| - It the pot should run out, simply crack open the pot with the pump running, and refill the pot. Subsequent refills will prolong the hold time as a greater thermal mass is cooled. |
| + It the pot should run out, simply crack open the pot with the pump running, and refill the pot. Subsequent refills will prolong the hold time as a greater thermal mass is cooled. |
| Line 413 was replaced by line 375 |
| - Temporary Close down |
| + ''Temporary Close down'' |
| Lines 417-419 were replaced by lines 379-380 |
| - 1. Ensure that the cryostat contains sufficient helium to last for the required period. |
| - |
| - 2. Ensure that there is no chance of the exhaust ports becoming blocked or iced up. The helium exhaust should be connected to a helium recovery system or vented through a one-way valve. |
| + # Ensure that the cryostat contains sufficient helium to last for the required period. |
| + # Ensure that there is no chance of the exhaust ports becoming blocked or iced up. The helium exhaust should be connected to a helium recovery system or vented through a one-way valve. |
| Line 424 was replaced by line 385 |
| - Warming the system |
| + ''Warming the system'' |
| Line 428 was replaced by line 389 |
| - Having adopted the above precautions, and with the magnet de-energized, the system can simply be allowed to run out of liquid helium and left to warm up. If a rapid warm up is desired, either transfer the helium out of the cryostat into a transport dewar or insert the blowing out tube into the transfer entry port and gently pass DRY helium gas through it. This will boil off the remaining liquid. |
| + Having adopted the above precautions, and with the magnet de-energized, the system can simply be allowed to run out of liquid helium and left to warm up. If a rapid warm up is desired, either transfer the helium out of the cryostat into a transport dewar or insert the blowing out tube into the transfer entry port and gently pass DRY helium gas through it. This will boil off the remaining liquid. |
| Line 434 was replaced by line 395 |
| - !5.1.1 Main Magnet |
| + ''5.1.1 Main Magnet'' |
| Line 436 was replaced by line 397 |
| - Symmetric Energisation: |
| + ''Symmetric Energisation:'' |
| Lines 440-532 were replaced by lines 401-434 |
| - |
| - Current for central field of 8 T |
| - Current for central field of 9 T |
| - 100.75 Amps |
| - 113.34 Amps |
| - |
| - Field / Current ratio |
| - 0.0794 T/A |
| - (794 Gauss/Amp) |
| - |
| - Nominal inductance |
| - 88 Henries |
| - |
| - |
| - Asymmetric Energisation: |
| - |
| - Guaranteed maximum central magnetic field at 4.2K |
| - Current for central field of 4 T |
| - 4.0 Tesla |
| - |
| - 91.35 Amps |
| - |
| - Field / Current ratio |
| - 0.0438 T/A |
| - (438 Gauss/Amp) |
| - |
| - Nominal inductance |
| - 46 Henries |
| - |
| - Neutron access |
| - 340 degrees in horizontal plane. +6 degrees I -6 degrees onto 24 mm on axis in vertical plane. |
| - |
| - Switch heater current for open state |
| - 75 mA |
| - |
| - !5.1.2.Resistance Values |
| - |
| - |
| - Room Temp |
| - 77 Kelvin |
| - 4.2 Kelvin |
| - |
| - Magnet resistance Start-End Sym |
| - Magnet resistance Start-End Asym |
| - 47.4 W |
| - 45.6 W |
| - 35.9 W |
| - 30.8 W |
| - 0.1 W |
| - 0.1 W |
| - |
| - Persistent mode switch resistance |
| - Switch heater resistance |
| - 50.0 W |
| - 214 W |
| - 210 W |
| - 205 W |
| - |
| - Magnet to cryostat isolation (at 500v) |
| - >20 MW |
| - >20 MW |
| - >20 MW |
| - |
| - Main magnet to switch heater |
| - >20 MW |
| - >20 MW |
| - >20 MW |
| - |
| - Carbon resistors for lambda |
| - point refrigerator: |
| - |
| - |
| - |
| - |
| - R1 |
| - 142.0 W |
| - 163.0 W |
| - 976.0 W |
| - |
| - R2 |
| - 153.7 W |
| - 176.6 W |
| - 1021 W |
| - |
| - R3 |
| - 166.8 W |
| - 189.3 W |
| - 1015 W |
| - |
| - R4 |
| - 164.9 W |
| - 185.5 W |
| - 1062 W |
| + |Current for central field of 8 T|100.75 A |
| + |Current for central field of 9 T |113.34 A |
| + |Field / Current ratio |0.0794 T/A (794 Gauss/Amp) |
| + |Nominal inductance |88 Henries |
| + |
| + ''Asymmetric Energisation:'' |
| + |
| + |Guaranteed maximum central magnetic field at 4.2K|4.0 Tesla |
| + |Current for central field of 4 T |91.35 Amps |
| + |Field / Current ratio |0.0438 T/A (438 Gauss/Amp) |
| + |Nominal inductance |46 Henries |
| + |
| + ''Neutron access'' |
| + |340 degrees in horizontal plane |
| + |+-6 degrees onto 24 mm on axis in vertical plane. |
| + |
| + |Switch heater current for open state|75 mA |
| + |
| + !5.1.2.Resistance Values (Ohm) |
| + |
| + | ||Room Temp||77 Kelvin||4.2 Kelvin |
| + |Magnet resistance Start-End Sym |47.4 |35.9 |0.1 |
| + |Magnet resistance Start-End Asym |45.6 |30.8 |0.1 |
| + |Persistent mode switch resistance|50 |210 |205 |
| + |Switch heater resistance |214 |
| + |Magnet to cryostat isolation (at 500v)|>20 M|>20 M|>20 M |
| + |Main magnet to switch heater|>20 M|>20 M|>20 M |
| + |
| + ''Carbon resistors for lambda point refrigerator (Ohm):'' |
| + |
| + |R1|142.0 |163.0 |976.0 |
| + |R2|153.7 |176.6 |1021 |
| + |R3|166.8 |189.3 |1015 |
| + |R4|164.9 |185.5 |1062 |
LIN