1. NA62 CEDAR PMT Cooling Update Tim

2. Chiller Investigations Web search identified Huber as one possible supplier – Europe-wide – Popular at CERN UK sales outlet is Radleys – Mainly specialise in chemistry-related equipment – Main Huber product lines are re-circulating baths and low temperature re-circulators Identified Unichiller UC017-H as a possible solution for NA62 Visit by David Martin last week to discuss

3. Parameters ParameterValue Temperature-10 to +100C Cooling power1700W Heater Power2000W Flow @ 0 pressure27 lpm Max pressure3.0bar Stability0.1C SensorInternal or external PT100 Mass120Kg Dimensions (WxDxH)450x510x1231 Cost£6,300 (each !)

4. Control Options include de-mountable control panel allowing remote operation – Remote means Distance ~ 20m (not 200m) Interface is digital so there’s still intelligence in the chiller – Doesn’t get ‘round SEU issue Optional digital interface (ComG@te) – By-passes control panel – Interfaces via ethernet to PC – Control / diagnostic s/w available allowing control / monitoring at ‘user’ and lower level – MAY get ‘round SEU issue by Regular read out of control parameters & check against defaults Ability to re-write parameters whilst chiller’s running to ensure correct values – Big issue is whether the full memory’s all available and whether the software can be adapted to automatically check for errors

5. Control … 0-10V analogue output available for monitoring (via ELMB) – Raise alarm if temperature deviates too much? Beginning to ask ‘awkward’ questions which require ‘expert’ knowledge of Huber systems to confirm whether there’s a viable solution

6. Pumping Curve Recall Spec is – dP = 1.8b, flow = 6lpm – Power = 2 x 107W Pumping curve shows a maximum volume flow of 10lpm for dP=1.8b – Impact will be slightly larger inlet-to-outlet temperature rise

7. Summary Huber seemed like a good bet but…. – One UC017-H will just about cool the PMT arrays with an inlet to outlet rise of 0.25C but with little safety margin – The remote control panel does not solve the SEU issue – The cost is rather high (if we need two) – The issue of control/monitoring via ethernet would need further discussions with Huber experts to confirm if it is possible to diagnose SEU issues & re- write parameters/re-start chiller remotely. Will also start looking for an alternative…… !