Emerson AMS User Manual page 62

Overall Velocity, PeakVue, and temperature
July 2020
• 5 for service factor of 1.15 or greater
• -5 for either open or totally enclosed fan cooled (TEFC) motors, and service factor of
1.0
• 0 for either totally enclosed non-ventilated (TENV) motors or motors with
encapsulated windings, and service factor of 1.0
If elevation > 3300 ft (1000m), then:
T = T
rise
If T is less than or equal to 40°C (or unknown), then:
a
T = T
w
If T > 40°C, then:
a
T = T
w
If T is unavailable, assume that T
a
Next, calculate the generic alert thresholds based on the estimated winding temperature,
T .
W
T
f_fault
T
f_maintenance
T
f_advisory
Alarm levels
For open drip proof (ODP) motors:
T
f_fault
For totally enclosed motors:
T
f_fault
For all motors:
T
f_maintenance
T
f_advisory
Error indication and steady-state determination
• Do not use any data readings collected within 30 seconds of motor start up.
• Check for error indications:
—
—
• Steady-state is said to have been reached when, over any 5-minute time interval, the
maximum variation in temperature is less than 2°F.
62
{1-[(altitude (units of ft) - 3300)/33,000]}
rise
+ 40°C
rise
+ 40°C - (Ta - 40°C)
rise
= Fault level alarm temperature (°C) of the motor skin (frame)
= Maintenance level alarm temperature (°C) of the motor skin
= Advisory level alarm temperature (°C) of the motor skin
= 35.5366*Ln(T ) - 91.1571
w
= 37.2028*Ln(T ) - 102.8868
w
= T - 10°C
f_fault
= T - 20°C
f_fault
If T > 150°C, the sensor is shorted.
f
If T < -40°C, the sensor is open or the wire is broken.
f
is less than 40°C.
a
User Guide
MHM-97927-PBF
MHM-97927-PBF, DRAFT