LumaSense Technologies M67 - Manual (Page 19)

M67, M67S Manual
18
The best cooling and purging system will only be effective if it operates all the time the process is running. It is therefore good
practice to include some safeguards. The best protection for cooling and purging systems is a flow switch. This is more
effective than a pressure switch and faster than a thermostat in the case of cooling protection. Additional protection can be
derived from the provision of a rotameter flow meter and regulator. Any audible or visual alarms should be located where
personnel are routinely present so that remedial action can be taken in a timely fashion.
TABLE FOR DEGREES F
REL HUM % 20 30 40 50 60 70 80 90 100
AIR TEMP COOLING WATER (JACKET) TEMPERATURE
40 WATER FREEZING 33 35 36 37 39 40
50 37 38 40 42 44 45 47 48 50
60 43 45 48 50 52 54 56 58 60
70 50 53 56 59 61 64 65 68 70
80 57 60 64 68 70 72 75 78 80
90 63 67 72 75 78 82 85 88 90
100 69 74 79 83 87 91 94 97 100
120 83 90 95 100 105 108 113 117 120
140 95 104 112 117 124 127 133 NR NR
160 107 118 127 133 NR NR NR NR NR
180 123 134 NR NR NR NR NR NR NR
200 135 NR NR NR NR NR NR NR NR
TABLE FOR DEGREES C
REL HUM % 20 30 40 50 60 70 80 90
AIR TEMP COOLING WATER (JACKET) TEMPERATURE
4 WATER FREEZING 1 1 2 3 4
10 3 3 4 6 6 7 8 9
16 6 7 9 10 11 12 13 14
21 10 12 13 15 16 18 18 20
27 14 16 18 20 21 22 24 26
32 17 19 22 24 26 28 29 31
38 21 23 26 28 31 33 34 36
49 28 32 35 38 41 42 45 47
60 35 40 44 47 51 53 56 NR
71 42 48 53 56 NR NR NR NR
82 51 57 NR NR NR NR NR NR
93 57 NR NR NR NR NR NR NR
Table 1 - COOLING WATER TEMPERATURE AT WHICH CONDENSATION WILL OCCUR AS A FUNCTION ON AIR
TEMPERATURE AND RELATIVE HUMIDITY IN %
NOTE 1: If your cooling water temperature is below the temperatures in the above tables, condensation will form on the IR
thermometer.
NOTE 2: NR = Not recommended. Water temperature too high for IRT ambient compensation circuits to be accurate.
EXAMPLE: The air temperature is 100°F and relative humidity is 90%. Cooling water temperature is tap water and is running
at70°F. Will condensation form on the IRT?
STEP 1: Look up 100°F on the air temperature column at left.
STEP 2: Look up 90% RH on the top horizontal row.
STEP 3: At the intersection of 100°F and 90% RH see 97°F.
STEP 4: Since 70°F tap water is less than 97°F (dew point), condensation is guaranteed to form on the IRT.
STEP 5: Cooling water must be raised to above 97°F, or flow rate reduced or turned off to eliminate condensation under these
conditions.