Johnson Controls Frick vyper VYA PG -46, Service Manual

Page: 38 / 64

VYPER ™ VARIABLE SPEED DRIVE
OPERATION
S100-200 IOM (MAY 08)
Page 38
Example 3
What are the High Motor Amp setpoints if a 305 HP Vyper is
to drive a motor with 1.00 SF and a 340 Amp FLA? Using
the Values, determine whether Table A or Table B should be
used to calculate the setpoints.
SF 1.00 motors need to be derated by dividing the Nameplate
FLA by 1.15 for an Applied motor FLA. Therefore:
340 A / 1.15 = 295 A
Line Parameter Value
1 Applied Motor FLA 295 A
2 Applied Service Factor 1.15
3 Multiply (Line 1 x Line 2) 340 A
4 HP rating of Vyper Drive 305 HP
5 Vyper Amp Limit
If Line 4 is 305/254 HP, value is 380 A
If Line 4 is 437/362 HP, value is 565 A 380 A
6 Multiply Line 5 x 1.05 399 A
The Line 3 value of 340 Amps is less than the Line 6 Value
of 399 Amps. Therefore, use Table A for the calculation.
Table A
Parameter Equation Value
Load Inhibit =Applied Motor FLA x 1.1 324 A
Force Unload =Applied Motor FLA x 1.12 330 A
Warning =Applied Motor FLA x 1.13 333 A
Shutdown =Applied Mtr. FLA x 1.15 339 A
High Motor Amps
Load Inhibit 310
Force Unload 324 Delay
Warning 330 5 SEC
Shutdown 337 5 SEC
Example 4
What are the High Motor Amp setpoints if a 437 HP Vyper ™
is to drive a motor with 1.00 SF and a 552 A FLA? Using
the Values, determine whether Table A or Table B should be
used to calculate the setpoints.
SF 1.00 motors need to be derated by dividing the Nameplate
FLA by 1.15 for an Applied FLA. Therefore:
552 A / 1.15 = 480 A
Line Parameter Value
1 Applied Motor FLA 480 A
2 Applied Service Factor 1.15
3 Multiply (Line 1 x Line 2) 552 A
4 HP rating of Vyper Drive 437 HP
5
Vyper Amp Limit
If Line 4 is 305/254 HP, value is 380 A
If Line 4 is 437/362 HP, value is 565 A 565 A
6 Multiply Line 5 x 1.05 593 A
The Line 3 value of 552 Amps is now less than the Line 6 value
of 593 Amps. Therefore, use Table A for the calculation.
Table A
Parameter Equation Value
Load Inhibit =Applied Motor FLA x 1.1 528 A
Force Unload =Applied Motor FLA x 1.12 537 A
Warning =Applied Motor FLA x 1.13 542 A
Shutdown =Applied Mtr. FLA x 1.15 552 A
High Motor Amps
Load Inhibit 504
Force Unload 528 Delay
Warning 538 5 SEC
Shutdown 549 5 SEC