Spectral Instruments Series 800, Руководство пользователя

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Spectral Instruments
Pt # 2500- 18
The camera shutter connects to a Lemo connector that is available as LemoUSA
part number FGG.0B.302.CLAD52Z. The wire must not be bigger than 22-
gauge and the cable must be between 4.1 and 5.0 mm in diameter.
1.4.3 The Auxiliary Port
A 4-pin Lemo connector at the camera head provides for external control out of
and in to the camera. The current status of the camera shutter is provided as a
signal between pins 1 and 2 of the auxiliary port. When the shutter is open the
signal is + 5 volts. Otherwise it is 0 volts. A switch closure between pins 3 and
4 on the auxiliary port sends a signal to initiate an exposure when the camera is
in the "triggered exposure" mode.
The auxiliary connects to a Lemo connector that is available as LemoUSA part
number FGG.0B.304.CLAD56Z. The wire must not be bigger than 22-gauge
and the cable must be between 5.1 and 5.5 mm in diameter.
1.5 The Cooling System
1.5.1 System Description
The thermoelectric cooler that lowers the temperature of the CCD is sized
according to the load provided by the camera head configuration. The design
load is determined by the size of the CCD, the presence of a fiber optic
attachment or the distance between the CCD and the window. The operating
load is very much affected by the pressure inside of the camera head chamber.
The watts to be removed from the camera head by an external cooling liquid
supply vary according to the size of the TEC. TE coolers run between 30 and
150 watts. Cooling liquid at +20oC flowing at rates between 3 and 10 liters per
minute are sufficient for TE coolers at 30 and 150 watts respectively.
It is possible to supply cooling liquid at a controlled temperature by use of a
closed cycle refrigeration system. This is necessary in the event that the ambient
temperature is high. It is important to avoid bringing the inlet tube to the camera
head below the dew point because condensation would result and condensation is
always bad.
1.5.2 Hooking Up A Cooler
The camera is fitted with two ¼” Swagelock VCO fittings. Spectral Instruments
supplies a closed cycle refrigeration system as a cooling option. The liquid is a
50% ethylene glycol and 50% de-ionized water mixture. It is important that the
fluid used be non-corrosive to the metal camera head chamber. As a minimum, a
buffered solution must be used. Glycol is not required unless the system is
exposed to temperatures that could freeze.