EQ7 Series Instruction Manual - TECO-Westinghouse Motor Company
EQ7 Series Instruction Manual - TECO-Westinghouse Motor Company
EQ7 Series Instruction Manual - TECO-Westinghouse Motor Company
Create successful ePaper yourself
Turn your PDF publications into a flip-book with our unique Google optimized e-Paper software.
Nominal applied<br />
motor<br />
HP<br />
Nominal Applied <strong>Motor</strong> and Characteristic Factors when P99 (<strong>Motor</strong> 1 Selection) = 1 or 3<br />
Thermal time<br />
constant <br />
(Factory default)<br />
0.25 to 30 5 min<br />
Reference current<br />
for setting the<br />
thermal time<br />
constant (Imax)<br />
Allowable<br />
continuous current<br />
150%<br />
Output frequency for<br />
motor characteristic factor<br />
Characteristic<br />
factor (%)<br />
f2 f3 1 2 3<br />
Base<br />
frequency<br />
33%<br />
Base<br />
frequency<br />
33%<br />
69 90 90<br />
40 to 60<br />
Base 54 85 95<br />
75 to 125 10 min<br />
frequency 51 95 95<br />
150 or above 83% 53 85 90<br />
If F10 is set to "2," changes of the output frequency do not affect the cooling effect. Therefore, the overload<br />
detection level (F11) remains constant.<br />
• Overload detection level (F11)<br />
Data setting range: 1 to 135% of the rated current (allowable continuous drive current) of the inverter<br />
In general, set the F11 data to the allowable continuous current of motor when driven at the base frequency (i.e.<br />
1.0 to 1.1 times of the rated current of the motor.)<br />
To disable the electronic thermal overload protection, set the F11 data to "0.00."<br />
• Thermal time constant (F12) Data setting range: 0.5 to 75.0 (minutes)<br />
F12 specifies the thermal time constant of the motor. If the current of 150% of the overload detection level<br />
specified by F11 is attained for the time specified by F12, the electronic thermal overload protection becomes<br />
activated to detect the motor overload. The thermal time constant for general-purpose motors is approx. 5 minutes<br />
for motors of 30 HP or below and 10 minutes for motors of 40 HP or above by factory default.<br />
(Example) When the F12 data is set at 5 minutes<br />
As shown below, the electronic thermal overload protection is activated to detect an alarm condition (alarm code<br />
) when the output current of 150% of the overload detection level (specified by F11) is attained for 5 minutes,<br />
and 120% for approx. 12.5 minutes.<br />
The actual time required for issuing a motor overload alarm tends to be shorter than the specified value, taking<br />
into account the time period from when the output current exceeds the rated current (100%) until it reaches 150%<br />
of the overload detection level.<br />
Example of Operating Characteristics<br />
4-42