Amprobe IR-750 Infrared-Thermometer - Manual (Page 16)

12
1. Press SET and then press / to select relatively high emissivity.
2. Press SELECT to select MAX.
3. Enable motor and allow it to reach steady state operating temperatures.
4. Disable the motor if possible.
5. Measure the two motor bearing temperatures.
6. Compare the two motor bearing temperatures. Unequal temperatures or a high temperature can indicate
a lubrication or other bearing problem that is resulting from excess friction.
7. Repeat the sequence for the blower bearings.
Testing Belts and Sheaves
1. Press SET and then press / to select relatively high emissivity.
2. Press SELECT to select MAX.
3. Enable the motor and allow it to reach a steady state operating temperatures.
4. Aim the thermometer at the surface to be measured.
5. Start recording temperature.
6. Slowly move the thermometer up the belt toward second sheave.
• If belt is slipping, sheave temperature will be high from friction.
• If belt is slipping, belt temperature will remain high between sheaves.
• If belt is not slipping, belt temperature will reduce between sheaves.
• If inner surfaces of sheaves are not a true “V” shape, this indicates belt slippage and will continue to
operate at elevated temperatures until sheave is replaced.
• Sheaves must be properly aligned (include “pitch & yaw”) for belt and sheaves to operate at
appropriate temperatures. A straight edge or taut string, can be used to check alignments.
• Motor sheave should operate at a temperature consistent with blower sheaves.
• If motor sheave is at a higher temperature at motor shaft than at outer circumference, belt is probably
not slipping.
• If outer circumference of sheave is at higher temperature than sheave at motor shaft, then belt is probably
slipping and sheaves may be misaligned.
Checking Hydronic Radiant Heat Applications
1. Press SET and then press / to select relatively high emissivity.
2. Press YELLOW button to select MAX.
3. To locate radiant heat tubes in floor, temporarily elevate the loop temperature to create hotter spots for
identifying tubing runs.
4. Before releasing trigger, press YELLOW button to toggle between MIN, MAX, DIF floor temperatures and
record the temperature for future comparison and trending under similar conditions.
Measuring Grill, Register, or Diffuser Discharge Temperature
1. Press SET and then press / to select relatively high emissivity.
2. Aim the thermometer at the discharge air grille, register, or diffuser.
3. Measure discharge temperature.
4. Release trigger to freeze the temperature reading for 8 seconds and record this temperature.
5. Grille, register, or diffuser temperature should be equivalent to discharge temperature at the air handler.