A flameproof EEx "d" motor suitable for Class I, Zone 0 must not permit ESCAPE to the outside atmosphere of any flame or hot gas that could ignite the surrounding atmosphere.
Painting over the whole motor enclosure of any color will not restrict to pass ATEX inspection. No industry codes and...
Is a modification to the auxiliary contacts of GE/Multilin 369 relay in the motor control circuit of 4.16kV MCC can help to solve the problem of repeat-start inhibit should not be reported as a trip signal to the DCS?
The 778HP, 4kV blower motor was running, operations personnel were fine...
Last week during tuning adjustments of our DCS system, the GE/Multilin 369 relay reported trip instead of start inhibit. Note that there was no overload during the trip. Our operations personnel doubted the repeat-start inhibit was activated during a second re-start attempt during DCS “tuning”...
If plotted on your demarcated hazardous plans and elevation drawings that your perimeter camera is located or falls within the electrically classified area, i.e. Class 1 location (gases or vapors), then you will provide and install an explosionproof camera suitable for Class, Division/Zone, and...
Here are the findings that I can share with you guys just in case you will encounter such kind of issue.
During start-up, the starting temperature of the fan (blower) is lower than the gas temperature. When they increased the shaft output, then this is the cause of motor overloading, the 369...
NEC 110.3 Examination, Identification, Installation, and use of Equipment
(A) EXAMINATION. In judging equipment, considerations such as the following shall be evaluated:
(1) Suitability for installation and use in conformity with the provisions of NEC.
(2) Mechanical strength and durability...
Check and verify from the manufacturer if the SF6 insulated pad mounted switchgear you are planning to install in hazardous area is suitable for Class I, Division 2, Group D location.
Purging/pressurization method to safely operate switchgear in hazardous classified locations may not be...
kiribanda,
As per the sequence of event recorder at the control room, 4.16kV MCC sent signal to the DCS that the multilin 369MFR tripped the blower motor.
electricpete
Yes, you are correct, LionelHutz info are correct. The figure 5-7 on page 5-146 can be read in conjunction with Table 5-1: 369...
rhatcher
Nothing in page 153 saying that the relay will trip after 10sec at 6.0pu x FLA. Are you referring to Table 5-1: 369 Standard Overload Curves of page 5-147?
jraef
Yes, the discharge valve for reaction furnace was shut-off during start-up, however, the blow-off valve were required by the...
We are doing the commissioning of a direct online starter (DOL) 4.16kV, 778HP, 60Hz. medium voltage motor being used for a reaction furnace air blower. The airflow is controlled by a sensor which is upstream of the blower. The motor is tripping recently due to overload. Motor FLA=93.9A, LRA=564A...
The vendor will not charge you for asking the transformer impedance values. With reference to section 5.8 of ANSI C57.12.00 "Preferred standard values of impedance are INCLUDED in the product standards for particular types of transformers"
When you specify the preferred impedance for a given...
For a medium voltage cable, Type MV, NEC Art. 328.10.4 uses permitted cable to be direct buried in accordance with column 1 of NEC Art. 300.50.
For a 33 kV, XLPE, 1x400mm2, single core with aluminum wire armour applied helically over an extruded PVC outer sheath is suitable for the above...
safy2004
All armoured cables are suitable for direct buried installations, and there are no relations of the armour on how the cable is laid (i.e. trefoil or flat formation).
Check the depth, a depth of 750mm for 33kV seems to be a violation against ANSI/NEC or IEC requirement.
The...
VRLA (Valve regulated lead acid) or sealed Ni/Cd battery banks normally release hygrogen gas during high rate charging mode of the UPS rectifier charger. To remove the hydrogen gas, you need extract fans with associated ducts for gas collectors, you need also supply fans for fresh air. The...
It is not new to me as I have designed in the past for Substation building which is 4 meters above finished grade level for oil & gas processing plants.
This is a common practice for oil & gas facilities, for safety purposes, to elevate substations even further higher depending on the degree...
