Oops. Here are the instruction on the manual.
Set the status of the pump to CLOSED. At the suction (inlet) node of the pump add a demand equal to the required pump flow and place a negative demand of the same magnitude at the discharge node. After analyzing the network, the difference in heads...
I came across this instruction in Epanet Manual on "How to size a pump to meet a specific flow". After going through the procedure in the program, i ended up with an unusually high hydraulic head value at the discharge node. Could it be that i have misinterpreted the instruction?
Abby: After studying your link at
http://i32.photobucket.com/albums/d41/a_bee_normal/Malaysia_MCC.jpg
I have a question.
1) The calculated Cooling Load of 22,249 BTU/Hr @ 749 CFM should also be the minimum capacity of air-conditioning unit required?
Many thanks to abby, quark & abcmex for taking time to reply this thread.
I apologize for the lack of info as i wasn't the one who get to meet and discuss with the Client and Plant Specialist. My superior who went there was as clueless as me if not worst. The limited info were conveyed to me...
if i were to use pressurize the room with outside air, would i need a filter to stop dust and particles from being sucked in? if so, what kind of filter is normally used? howabout those filter that are normally used in a AHU unit?
The 85% RH ambient plant condition and the required 45% RH for MCC Room is actually given by the fertilizer plant specialist from India who were going to install all the equipments. It was based on their experience according to them. hmm... seems like i'll need to have a discussion with them...
Your friend must be having a good holiday around those places. LOL.
On the sensible heat load, electrical heat gain from the switchboard would be about 10,243 BTU/Hr. Assume that infiltration and occupant load is negligible, what other load should i consider as sensible load?
Correct me if...
Im from Malaysia and its basically hot and humid here. so if i were to size an air-cond unit, the btu/hr of the unit should be equivalent to the [rate of sensible heat transfer + rate of latent heat transfer] in changing the temp + RH of the mixed air to desired room temp. + RH ?
Thanks a lot for your help Abby. What would most likely be the source of latent heat? could it be the 10% of outside air intake by the air-conditioner? The switchgear should be the largest contributor of the sensible load right?
Also, you're saying that i should size the air-cond. unit based...
The Client has proposed to install split air-conditioning unit in the MCC rooms of a fertilizer factory for the purpose of cooling as well as dehumidifying the space to avoid dust and particles + water in the air to attach itself to the switchboards and therefore affect the insulation. My...
waross: according to the manufacturer catalogue, the DOL starting current is 8x the FLC. if i were to size my breaker to 200% - 250%, wouldn;t it trip the breaker during starting ? im a bit confused now because i just read a book saying that circuit breakers must be sized to take the starting...
thanks a lot to itsmoked and waross for the quick reply.
So based on the motor / pump load, what kind of starter is hest for me? DOL , Star-Delta or AutoTrans ? Is it true that if i were to select DOL, i'll have to size my breaker to 8x the FLA of the pump ? and howabout for S/D starter?
im rather new in this field so please forgive my ignorance. im not so sure of the LRA but from the manufacturer catalogue, the DOL starting current / Nominal Current = 8.
