Write a new entry for the Guestbook

Fields marked with * are mandatory. Your E-mail address will not be published. For security reasons we save the ip address It might be that your entry will only be visible in the guestbook after we reviewed it. We reserve our right to edit, delete, or not publish entries.
39 entries.
Dimas Serrano Dimas Serrano wrote on February 15, 2018 at 2:58 AM:
Engr. Ver good morning po. Tanong ko lng po, ilan po ang minimum allowable distance ng poste ng meralco sa property line ay any part ng bahay ko. Salamat po.
Chito Serrano
Admin Reply by: Ver Pangonilo
Chito, kung ang pagbabasehan ay ang PEC, sa aking kaalaman ay walang nakasaad na minimum allowable distance from the property line. Pero meron itong provision on horizontal clearances of wires and cables for other structures is 1.5m (ref. PEC 2 - 2008 Clause Kaya nasa sa iyo na yun kung papayag ka na magtayo ang Meralco ng poste sa property mo.
Ella Ella wrote on December 20, 2017 at 1:16 PM:
Where to find a book?

Philippine Electrical Codes Volume 1

Admin Reply by: Ver Pangonilo
You can buy it from IIEE (
Joefrey Joefrey wrote on November 23, 2017 at 6:50 PM:
tanung lang po
1.0 anu po ang maximum allowable na ampacity sa switchgear (low voltage).
2.0 maximum acb rate is 6300A for low voltage application, anupong susunod na device lets say for 10000A protection, are there any.
maraming salamat po
Admin Reply by: Ver Pangonilo
It is best to consult Standards (IEEE, IEC, etc) for your question. In my designs, I used a maximum of 3200A ACB rating. Larger than that, there will be lots of issues concerning busbar sizes, temperature rise, etc.
shaun shaun wrote on October 30, 2017 at 10:33 PM:
Good day Sir,

I have a problem with VSD failures at one of my sites (a shopping centre). The system consists of an 11kV incomer and many 11kV / 400V distribution transformers.
Power readings indicate an imbalance of voltages on the 11kV incomer terminals.
Where should I start for diagnoses?
Admin Reply by: Ver Pangonilo
The very first thing that you should do is to inform your power provider of the 11KV imbalance. I believe that the culprit is on their side. To protect your VSDs, you should install an undervoltage / single phasing protection relay on the VSD feeder breaker. This protection relay will trip if a voltage imbalance occurs protecting your VSD.
reagan ramos reagan ramos wrote on October 26, 2017 at 2:50 PM:
good day sir,
ask ko lang po if pwede po bang pagsamahin ang set of wires from load and line side sa iisang conduit na RSC?

salamat po
Admin Reply by: Ver Pangonilo
Using good engineering practice, you should not combine line side conductors and load side conductors in a single conduit.
Erwin Directo Erwin Directo wrote on October 19, 2017 at 1:58 PM:
Good day Engr. Ver!

just passed by to say thank you..i found your site few years ago and your site really help a lot..

God bless..
Admin Reply by: Ver Pangonilo
It's good to know you found my site helpful. Thanks for dropping by.
steven haskins steven haskins wrote on August 31, 2017 at 6:05 AM:
I am having trouble correlating motor class insulation and its relation to B rise and F rise. For example, can you have a 65 degree ambient with Class F insulation and meet B rise, why or why not?
Admin Reply by: Ver Pangonilo
In IEC 60034-1:2004, Table 10, the maximum ambient temperature for Class B & F is 40 deg.C. The temperature rise are 130degC (Class B) & 155degC (class F). This means that the 65degC is unacceptable based on this IEC std.
Nems Nems wrote on August 30, 2017 at 4:09 PM:
Sir Ver
Good day, im working in hospital facility, voltages in our distribution line are L1N=115v, L2N=120v, and L3N=220v, but the line to line voltage is 230v, QUESTION-what do you think is the problem. any suggestion or recommendation please. thanks
Admin Reply by: Ver Pangonilo
I reckon that your system is Wye ungrounded with unbalance load. Check the current of each line to verify the load of each line. To solve this problem, ensure that you have asolidly grounded neutral.
Alex Bogias Alex Bogias wrote on July 26, 2017 at 1:28 AM:
Hi Ver,

The book you have titled "Introduction to Power System Protection" is not the "Practical Power Systems Protection".

I suspect its from people from Schweitzer Engineering Laboratory (SEL) but I simply can't find it.

If you have any ideas please let me know.

Thanks and regards
Admin Reply by: Ver Pangonilo
In my recollection, I believe that this book was given to us as a reference in one of the training I attended but I could not remember which one.
Pablo Jabajab Jr Pablo Jabajab Jr wrote on July 13, 2017 at 12:28 AM:
Greetings Ver!

It’s my pleasure to have your contact.

I have query regarding the time-curve characteristics of the circuit breakers.

I prepared a circuit breaker coordination considering LSIG trip unit protection from downstream to upstream.

How to prepare time current curve in excel format? Is there available software for this particular requirement? Please advise.
Admin Reply by: Ver Pangonilo
Search my site and, you will see tutorials on how to do time current curve in excel.
Alex Bogias Alex Bogias wrote on May 26, 2017 at 10:29 PM:
Hi Ver,

The book titled "Introduction to Power System Protection" is of interest to me and I would like to purchase it but I believe that is NOT its title.

Do you by any chance know its official title?

Thanks and regards
Admin Reply by: Ver Pangonilo
Try this book
Practical Power Systems Protection
Author: Les Hewitson
Ravi Prakash Ravi Prakash wrote on May 19, 2017 at 2:27 AM:
Sir, I am sorry for not giving all detail about the design of transformer. The detail of transformer are as:
A 2 winding 3 phase transformer of 33kV/440V, 2MVA has short circuit voltage is 6.5%.I have to put the right value of short circuit power in software so that transformer can operate with minimum loss.
I have applied common approach but not getting right value. Please let me know some approach.
Admin Reply by: Ver Pangonilo
Are you trying to design a transformer, want to create a transformer specification or doing a fault analysis using the transformer you mentioned? What are you trying to achieve?
Ravi Prakash Ravi Prakash wrote on May 18, 2017 at 4:26 AM:
I have to know about design of two winding transformer.
SC Voltage
Admin Reply by: Ver Pangonilo
With such a little detail, I am sorry but I could not help you.
Richard Richard wrote on May 10, 2017 at 10:36 AM:
My questions is, if your building has a large load and you are advised by the power provided to have a separate power supply. Who's responsible in providing transformer and KWH meter. Is it the customer or the power provider. Thank you.
BG BG wrote on May 7, 2017 at 2:27 PM:
Hi Sir,

Thanks for the info, but how about cells C10 to C17? Looks like interpolation to me, since values were taken using long time pick-up and instantaneous pick-up, but I think I am missing something. Sorry to bother you, I really wanted to learn this excel stuff. This will be very useful for my PEE TER without using ETAP.

Admin Reply by: Ver Pangonilo
You are exactly right. Having known the two extreme points, the middle points are interpolated between them using the values from column A. Again the only reason for this is to have a smooth curve when plotted.
BG BG wrote on May 4, 2017 at 6:26 PM:
Hi Sir,
It is the one that I downloaded in your website sir.
Here's the path:

Admin Reply by: Ver Pangonilo
The values on Sheet 3 Cells A9 to A18 are arbitrarily selected to provide a smooth curve when plotted. You can select any values you want. All other entries are calculated.
BG BG wrote on May 4, 2017 at 12:47 AM:
I just want to ask something in the attached excel file for Time-current curve, Sheet3, Cells C10 to C17. Are these values interpolated? I also want to know how did you arrive for the values in cells A9 to A18 Sheet3.
Admin Reply by: Ver Pangonilo
Can you provide the link to the article you are referring in your query?
merek merek wrote on March 14, 2017 at 12:46 AM:
Hello, sir!
I don't know how to modelling autotransformer in ETAP. It's possible to modelling autotransformer?
Thank you!
Admin Reply by: Ver Pangonilo
ETAP does not explicitly model auto-transformers.
Dipon Dasgupta Dipon Dasgupta wrote on March 7, 2017 at 11:02 AM:
I'm performing a coordination study on a distribution at my school. I'm not sure how to estimate or calculate the MVAsc or X/R ration of our utility. Please help if possible. Thank you.
Admin Reply by: Ver Pangonilo
The best method is to ask your utility about these parameters.
eng ah.ase eng ah.ase wrote on January 2, 2017 at 12:04 AM:
hi, my sir
iam from iraq electricls eng
i cant understanding the time and current
curve tripping i need pdf examples description prosiduer for the curve if you could help mi
i will be very glad from you and thank to you

Facebook Auto Publish Powered By :