Monday 20 January 2014

KAIRA frozen

Yes, it is the Arctic, but for the most part, KAIRA copes with the cold. Having a lot of warm signal processing electronics and computers keeps the inside of the RF container pretty toasty. However, in the early hours of this morning, we came unstuck.

Due to a computer failure, we scheduled a 5 minute UPS power cycle to reset the station. In the end the outage lasted a total of 7 minutes. Following the re-establishment of power, we did not recover the cooling system. Our suspicion (although we are still working on testing and checking this is that during the outage, the load on the air-conditioning dropped, thus allowing the low outside temperatures (approx. -35 deg C) to adversely drop the pressure of the refrigerant. This caused an air-conditioning failure.

Outside temperatures. The UPS was shutdown at approx. 0400 on 20-Jan-2014.

The irony is that, when the power was re-established, the internal computing and electronics overheated. Made even worse by the near-zero humidity, giving little heat transfer capacity to cycling air. The final error message before the system self-shutdown to protect itself indicated an internal temperature of 35 deg C... some 70 deg C greater than the outside ambient!

Within an hour of this shutdown, the temperature will have plummeted again.

We have checked the site today, but there is not a lot we can do without major work. Our best chance is actually to wait for some forecast warm weather ("warm" means > -25 deg C), which is expected later this week.

In the meantime we are off air awaiting the better conditions.

Such are the hazards of Arctic operation.

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