3.8 SWS90-SWS98 - Engineering Observation

The SWS90-SWS98 were short sequences of commands for activation, de-activation and routine monitoring of the instrument, under direct control of the instrument operators. They are of little interest for observers but are included here for completeness.

They were:

SWS90: SWS switch-on and complete RAM load. Leave the detector biases switched off.

SWS91: Try and cure the detectors by heating the detector substrates to the maximum values (for this purpose electrical heaters were glued on the substrates).

SWS92: Switch on the detector biases, put the instrument in its default operational state.

SWS93: Try and cure the detectors by irradiating them with photons from the `flashers'. For bands 2-6 this would have had no effect without the bias switched on.

SWS94: After the instrument has stabilised, or at any other moment, take a dark current measurement and then return the instrument to its default operational state. Introduced at the end of January 1996.

SWS95: SWS post-helium band 1 detector setup sequence.

SWS96: SWS post-helium band 1 internal wavelength calibration sequence.

SWS97: SWS post-helium band 1 internal grating calibration sequence.

SWS98: Switch off.

SWS99: Reserved for the CUS/post-helium.

At the start of a revolution SWS90 to SWS94 were executed in sequence to set the instrument up. SWS98 de-activated the SWS at the end of a revolution. For the post-helium revolutions SWS95 to SWS97 were used to activate the instrument, with SWS98 still used for de-activation.