1. 27/11/02Paul Baillon wach4 2002 Paris1 Heat transfer study in M0’ using the thermistors on the APD’s and on the boards

2. 27/11/02Paul Baillon wach4 2002 Paris2 Starting the electronic. Calibration of the APD’s

3. 27/11/02Paul Baillon wach4 2002 Paris3

4. 27/11/02Paul Baillon wach4 2002 Paris4 Elec. off Elect. on   Power cooling water The flow is 0.14 liter/s. The cooling power for 0.42  (out-in) is 2.5W/channel. in out

5. 27/11/02Paul Baillon wach4 2002 Paris5 in out 0.013  Elec. offElec. on Regulating cooling water The flow is 0.22 liter/s. The cooling power for 0.013  (out-in) is 0.12W/channel

6. 27/11/02Paul Baillon wach4 2002 Paris6 Power cooling Failure on the main cooling circuit on 23/9/02 Effects on the temperature of the electronic and the APD’s

7. 27/11/02Paul Baillon wach4 2002 Paris7 out in 1.29 

8. 27/11/02Paul Baillon wach4 2002 Paris8 Boards Apd’s 0.03  11

9. 27/11/02Paul Baillon wach4 2002 Paris9 in out Regulating water Temperature increase 0.005 

10. 27/11/02Paul Baillon wach4 2002 Paris10 Conclusions: Temperature of APD (Thermistor) is 0.1  above cooling water when the electronic is on. When the water of the power circuit has its temperature increase by 1.34  : -Temperature of APD (Thermistor) is 0.1  above cooling water -The outgoing regulating water increases its temperature by 37% and the APD’s by 30%. -The connector of the APD (on the board ) has its temperature increased by 1.34  at maximum. (it cannot be higher than the increase of the power cooling ). All the heat going to the regulating circuit and to the APD’s goes through that connector. Then we deduce that the connector has a temperature less than 1.34/0.3=4.4  (above the regulating water.)

11. 27/11/02Paul Baillon wach4 2002 Paris11 Effects on the APD’s of power variations in the electronic. It is due to a low voltage variation correlated to temperature variations in the control rack in the barrack.

12. 27/11/02Paul Baillon wach4 2002 Paris12 board APD thermistors 0.012  0.12 

13. 27/11/02Paul Baillon wach4 2002 Paris13 Conclusion: The rise of the board temperature is clearly correlated to a rise of the low voltage power supply and of its current. The rise is 4% in temperature of the board to which corresponds 12% rise on the APD thermistors. There is more power consumption and heat release at the bottom of the board (FPPA?)