Telemark TVP-2000, Руководство по эксплуатации, установке и обслуживанию

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TVP Manual (full) March 2007 CE rev 03.doc
2.51 Starting the unit for the first time
Reset the STOP button after actuation it must be turned 90o clockwise, all other buttons have
a momentary action. The TVP will automatically reset after a forced stop, manual start or
renewed remote start signal are required for restart. If the unit is ready for operation the
green start / standby button will illuminate.
Depress the start / standby button the unit should run, the display should read Pre-cool, check
the value for DP rises and the value for SP falls. If the unit has the wrong phase orientation
DP/SP values will not change significantly, switch unit off and isolated at supply. Swap two of
the phases to correct phase rotations and restart unit, if correctly installed the unit will also
run noticeably quieter.
If the unit fails to start check the over pressure trip (diagram 3.) And reset if necessary by
sliding the green re0set button. Failure to start may also be caused by the phase protection
check software error message on display and restart.
2.52 Evaluation of TVP after initial installation
The water temperature rises (higher outlet vs. Inlet) check flow is in correct orientation
DP rises to more than 400 psi and then drops
SP falls
Coldest temperature (CT) falls rapidly to a value of less than –70
o
c.
System will enter ready to cool state (green light illuminates) in around 30 minutes from initial
start-up. At this point approximately 70% of the maximum cooling capacity is available. A
further period of standby until the value of DP is less than 180 psi.
Run system until stable check that:
SP reaches 27 psi or less and DP achieves less than 170 psi. If the water temperature is lower
than 20
o
c values for DP and SP will also be lower. If the value for SP falls below 3 psi during
any extended period of Standby operation the system may be short of gas and a leak should
be suspected.
WT must be less than 32
o
c in Standby.
2.53 Cycle the water vapor cryo-trap
The purpose of carrying out several cycles is to induce any small leaks in the couplings before
the system enters service. This way maximum productivity is assured.
Cool
Refer to the operation section of this manual, evacuate the vacuum chamber to a depth of 5 x
10
-3
mbar (cross over temperature)
The system is ready to cool. Press the COOL button to start cryo-pumping. The CI and CO
values will stabilise the temperature differential between CI and CO of up to 20
O
C is possible
when the system is under maximum heat load. The exact differential between CI and CO is
dependent upon many factors including the length and quality of the insulation of the
refrigeration lines. During a cycle where no heat from in chamber processes is being absorbed
the differential should be less than 5
o
c.
Allow system to stabilise ideally for 1 hour and note system parameters DP, SP, WT, CI, CO
and ultimate vacuum level for future reference.
CAUTION
Ensure the cryo-coil is located in a vacuum chamber and that the chamber is evacuated to at
least 0.005 Torr or 5 x 10
-3
mbar to prevent overheating and excessive frosting of the coil from
latent heat.
Defrosting
After cooling the cryo-coil is regenerated by defrosting. This is achieved by pressing the
DEFROST button. Note time taken to defrost. During any of the pre production phases it is
very useful to use the data logging facility of the TVP for future reference and timings.