Thanks for the very useful information given about the probable applications. All Electrical Systems are interlinked with certain application. Hence our solutions should always consider the requirements of final application.
Did you think of replacing the Pump-Motor as a unit? Whether any specific need for running the Pump at 150 RPM? If not we can consider replacing the Pump- Motor operating at 1500 RPM. The size of the Pump will be reduced to 1/10th. The system will operate at better efficiency. The spares for...
Vacuum contactors are always chosen with fuses for short circuit breaking. Contactors takes care of only overload. And they should be able to withstand the shortcircuit till the fuse is blown. so any tating of app. 5 - 6.5 ka should be sufficient. Details are to be worked out for individual systems.
For lamps, the drop in voltage is half of the total voltage drop in the conductor from the source to the lamp and back. Hence the voltage drop at lamp terminal id (dc VD/2). Lighting loads can not be operated with 3 wire system.
For motor loads the line current ( or the line voltage ) is...
U can contact either Predict or CSI for their product. This instrument is useful to detect rotor bar breakage when the motor is running.
Simple test is to do the hammer test - Keep a multimeter in resistance range across the suspected broken rotor bar. Hammer the bar with a little force. If...
Dear alocade,
For measuring the physical center it is easier to push & pull the shaft when the motor is running instead of stopping.
Simple pencil can push the shaft as the shaft is floating on the oil film. Rotating the shaft in stationary condition may score the bearing surface.
In the vector version of VFDs the magnetising (field) current generating the magnetic flux is "independently" controlled both magnitude and phase angle.
Once the phase angle is at 90 degrees to the load current the maximum torque is developed. Also as the magnitude of the field current...
Thank you every one for your valuable comments.
Certainly VFDs are understood by engineers. When we are in the age of "Prevent Maintenance" VFDs are preferred as their reliability is very high with minimum or rather no maintenance. As on date the electricians may not understand and...
Some of the requirements which are required to be met as indicated are better met by SqIM along with VFD.
Easy to fix- No rotor resistance, Rotor cables , Rotor contactors . Only a Sq. cage motor with 3 leads connected to VFD.
Simple parts & simple equipment - What is nmore simpler than SQIM...
Motor controlled by VSD can develop 100% of full load torque at all speeds below the rated speed unlike the pullout torque occuring at only at one speed by a Sq. Cage motor with DOL/Soft starter.
On operational point of view Motor with VSD can be used in any applicaion. If the torque required...
The load torque of a pump during starting varies from 0-25% when the inlet/ outlet valve is fully closed, varies from
0-50% when the valve is app 50% open and 0-100% when the valve is totally open.
The starting characteristiscs of the motor does not change but the starting time will increase...
WRIM with resistor grid / Liquid resistor is a "Load dependent" drive. The torque developed at various speeds is dependendent on load hooked. SCIM with VFD is load independent and developes PULL OUT TORQUE at ALL speeds.
The current requirement is based on the load and the power...
In a pump either the head or the flow is more than required by which the motor power is much more than required. Please check the existing pump characteristiscs and the actual requirements. It may B possible to achieve Ur requirements with the same motor & different pump
For our stacker and reclaimer of our Yard machines we propose to replace the existing control cables used for communication and interlocking with Radio communication. The no of inputs and outputs may be 16 digital and 8 analog.
Kindly indicate probable suppliers with their communication...
