HPU issues xlx

[Darrell Downing]

Hope someone can help with this issue
XLX system,
as we fire up hyds on the rov, we get a reading of 50amps + and then the systems shuts down including the topside mediawall, and subsea controller

Im unsure why its drawing that much amps
Genny is a750kw so it should be more than ok

we are using t32 oil but we are working in a cold climate.
22 would be better but not available.
any suggestions on the cause and the cure
regards

[Mike Kidd]

You can check your transformer tappings, raise the voltage you see a reduction in the current to the motor, hope this helps..

[DANFROV]

The MAX current you can draw on the XLX is 30 Amp. ( This can be adjusted in software by entering the configuration mode. on HMI. Just tap Pump pressure dial. )

On start up you have an auto function whcih gives the vehicle a Hydraulic soft start.

There is no electrical soft start.

PDU Inputs
Three phase 440V supply
Single phase 120V AC supply (from console UPS)
Control signals from remote on/off panel
Winch purge failure signal (if system is a Zone 2 rated system)
PDU Outputs
Console 120V supply (2 off 120V supplies at 21 A each, a total of 5kVA)
HVJB 120V supply (1 off 120V supply at 3A)
ROV instruments surface transformer primary (10 380V- 480V at 8.5kVA)
(TXLX subsea ROV instruments requires 10 3000V at 2.6A (8kVA))
ROV HPU surface transformer primary (30 380V- 480V at 200kVA)
(TXLX subsea HPU requires 30 3000V at 29A (151 kVA))
TMS instruments surface transformer primary (10 380V- 480V at 1.5kVA)
(TMS subsea instruments requires 10 2400V at 0.5A (1.2kVA))
TMS HPU surface transformer primary (30 380V- 480V at 15kVA)
(TMS subsea HPU requires 30 2400V at 2.6A (1 0.8kVA))
evet ythmg remotely possible
a J’

DanFrov

[turtle]

I’m wondering where you are reading the 50a on start up. Is system tripping or is genny sensing overcurrent causing supply to system to be interrupted? New rental genny or one that has seen constant past regular service? If it’s a genny that’s new to system confirm if there are software max current limit settings on output of genny.

Otherwise sounds like you may need to check the HPU — any recent mod? repaired/replaced? recent history of seawater intrusion? checked all lines and HPU for insulation integrity?

Drop a note if you get a chance after all back on line…last resort spit in the back and kick it….make sure boots are well insulated

[Darrell Downing]

Yes reading 50+ amps on start up and the genny groans like a bugger
console and topside shut down is due to winter in storage and i reckon ups completly drained.
Ive asked vessel to piggyback gennys but they wont play the game.
Will check filyers and start from there and see if any tale-tell signs. I dont think there will, be as system only 1 year old.
ailing that, i will see i 22 grade is available or the colder temps but ive worked in romania in colder than this and never had an issue.
cheers guys, will be in touch after a few tests

[Darrell Downing]

have checked filters and they are good. no particles or metal
When fired up hpu this morning, the PDU dropped to 398v on the initial start and then went back to 440 on L1 L2 L3

Current went to 60Amps!!! then dropped to 11 once running.
Still investigating
any other possibilities???

[HelpMaBoab]

Aye,
Sounds like you have a duff Genny if the voltage is dropping that much.
Are you sure its not a 300kva gen with 750kva badges on it???

[Sit Rep]

Not familiar with the XLX however..

Can you dial down the system pressure prior to startup via software? This might allow the HPU to start up in a bypass situation and reduce starting current.

Additionally, even on the old Tritons HPU current is up around 90A when loaded so if the genset can’t handle that you’ll have problems.

Are you able to change the AVR mode on the genset either manually or automatically?
Cheers

[Darrell Downing]

Will try to adjust AVR
Also was thinking of increasing genny voltage to 450v on each phase as this may get the system passed 400v to work and stop the 110v contactors shutting down.
Thatll be just over 10% so i hope the genny will drop no lower than 410v
Just an idea

[DANFROV]

It is NOT Possible to bypass the start up function on the HPU on an XLX, The Pump goes into start mode for 5 to 6 seconds. After this you can change to manual pump control and set the pump pressure to anything you want from 500 PSI to 3500 PSI.

DanFrov

[Author]

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