Power Quality

[admin]

Hey,

 

I have two different server racks connected with two different phases vis different MCBs. Source DB is same. Recently we have experienced tripping of MCBs of both racks with in One minute time delay. Input supply is from latest version of MGE UPS systems.

Not able to find out the reason. Can some one explain the reason?

[s]

Try to analyize the power quality and measure the THD ( total harmonic distortion) 

[Spir Georges GHALI]

VNR said:

Hey,

 

I have two different server racks connected with two different phases vis different MCBs. Source DB is same. Recently we have experienced tripping of MCBs of both racks with in One minute time delay. Input supply is from latest version of MGE UPS systems.

Not able to find out the reason. Can some one explain the reason?

---

Dear ;

 

Please let me know if this One minute time delay is between the 2 MCB's, or both MCB's trip at the same time but this delay is more than a previous recorded tripping time.

[admin]

My name Istvan fro Hungary and I met with this problem in my practice. If the protection are designed well . look aroud the installation. The  output of the MGE ups (tree phase ) mostly has a neutral in the output , and there is an earthing . One case a costumer led the tree phase and the earthing from the UPS to his devices , and the star connetted output transformer's star point were not conneted. There arised a virtual star point , the earthing wire , and the different phase voltage set by  the ratio of the  the loads by phases . The line voltage were constant, only the phase voltage were changing between 100 and 500 V . The result was same what You described.

[Author]

Posts