Protecting 1400HP Motor with 369 Relay

[SixOn]

I would like help protecting the motor with the following data on the name plate:

MOD : MGA 6811
NA : 1679410707
HP : 1400
RPM : 1487
Hertz : 50
VOLTS : 6900V
AMPS : 103.7A
DUTY : S1
INSULATION : F
IL/IN : 7
SF : 1.15
COS : 0.88
AMB : 50°C
FTM : RISE 70°C

We have an Motortronics MVC3 Soft Starter & a Multilin 369 Relay.

For the MVC3 I need help understanding the Setpoint Page 8 settings.

My understanding is that the LRA is 700A.
SP8.1 & SP8.2 has the run curve locked rotor time & start curve locked rotor time set to the overload curve selected in SP1.3
Are these the time I read under 7FLA on the overload curve?
What acceleration time limit, number of starts per hour and time between starts would you recommend?
As for SP.12 Do I read the time for the cold and hot stall time from the overload curve under 7FLA?

Now going to the 369 Relay

How do I choose the VT ratio needed under Setpoint 2?
Do I need to match the S3 running cool time constant and stopped cool time constant to that selected in the MVC3 SP.12?
Should I also match the S3 hot/cold safe stall ratio to that of the MVC3 SP.12?
Should I also match the S5 start inhibits to those selected in the MVC3 SP.8?
As for S7 over/underfrequency, what is the acceptable deviation from the 50Hz acceptable?
Should I match this to the one selected on the MVC3 SP3.11?

 

[jraef]

The MVC3 starter has all of the functions of a realy 369 buit-in. Adding a 369 is completely redundant. Yet people do it because they are familiar with the 369 in other applications in their facility and want consistency, nothing wrong with that if you are willing to pay the addition money.

However from your questions I gather that you are unfamiliar with both products, in which case you likely wasted your money adding the 369. Be that as it may, I would default the motor protection to the 369 since you have both now, because if the MVC3 board goes south for other reasons, you at least still have that. Although the MVC3 board will open the line contactor if anything goes wrong, you may also lose the record of what the problem was if the board suffers a catastrophic failure, the 369 would retain the last state in memory, separate from the control board.

I therefore would NOT match the settings between the two, because then you just set up a race between them and in troubleshooting, you do not want potentially conflicting information. Set the 369 parameters, then go back into the MVC3 and set those slightly higher or disable them.

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[SixOn]

I do get the part where it would be catastrophic to match the setting.

The only thing that would help me now is if I can get my hands on the motor datasheet.

Do you have any idea where I can find it. I have been searching and I'm yet to come accross it.