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  1. Run1on

    Electroflow

    Has anybody had any experience with a product called ElectroFlow? A client of mine has been approached by a distributor who claims his equipment can decrease kw consumption by up to 34% and do a host of other power conditioning items. I find it VERY hard to believe any one piece of equipment...
  2. Run1on

    Retorque of bolted electrical connections

    I am from the camp of retorque when thermal testing indicates. If the system was properly torqued and tested when installed ( most equipment manufacturers have standard torque values for their equipment) there should be no additional problems unless you believe the system has been...
  3. Run1on

    Capacitor Bank Placement

    SMLD: I can help you with your customers problem. As the others have discussed there are a lot of issues to installing a capacitor bank in any system especially one with nonlinear loads. Run1on
  4. Run1on

    Chiller VFD installation

    Thanks, David. As far as I have been able to determine York is the only manufacturer that has taken on solid state controls for screw chillers. I have been told that due to the pressure imbalances that can exist in a screw chiller (front to rear) it is a difficult design challenge to achieve...
  5. Run1on

    Chiller VFD installation

    The chiller in question is a Trane model RHTB 300 ton unit 274 KW, 480 v Run1on
  6. Run1on

    KW demand vs. chiller operation

    Busbar: The current imbalance issue is still out to lunch. We installed metering at the utility transformer and watched for several weeks. There was no evidence of voltage imbalance incoming. We then proceeded to thermal scanning (IR camera) and found some problems that have been corrected. Our...
  7. Run1on

    Chiller VFD installation

    All you HVAC engineers! Question? Can a VFD or soft start controller be installed on a Rotary Liquid Chiller? I have received conflicting info regarding this action. We are trying to reduce the initial elec. demand on startup. Any ideas? Run1on
  8. Run1on

    KW demand vs. chiller operation

    I appreciate all the useful info on the subject. For the record, we are also on a ratchet structure where the highest demand (15 min. interval) recorded during the previous year establishes our baseline for the following year. The chiller in question runs nowhere near its 100 % limit, typically...
  9. Run1on

    KW demand vs. chiller operation

    We have been investigating our power bills and have discovered we are on a 15 min. demand timer arrangement. When our 300 ton chiler starts it develops an inrush current of approx. 800a ( sometimes 1000) As such the demand meter "sees" this point and registers it. Is it possible to...
  10. Run1on

    Current imbalance in three phase chiller motor

    peterb: I find that conclusion highly plausible. This school renovation was repeated at two other schools with the same design firm and electrical contractor. It is very possible When I have the results of the further investigations I'll post them. It helps greatly when a question is posed and...
  11. Run1on

    Current imbalance in three phase chiller motor

    Thanks for all the input. To answer some of the useful questions posed: 1) The chiller runs reasonably well after startup; it has a problem with cycling that needs to be addressed by the manufacturer. 2) We just finished checking other feeders from the MDP and found current imbalance on almost...
  12. Run1on

    Current imbalance in three phase chiller motor

    It seems that the problem lies potentially in the electric system. Diagnosing problems is undercover work. We have found out that the chiller technicians "rolled" the leads to the chiller at the breaker located at the MDP and the imbalance stayed with the phase not the motor. We are...
  13. Run1on

    Current imbalance in three phase chiller motor

    I have some more information to pass along on this subject. We received downloads from the chiller unit and compared time frames on the voltage and current levels. When the chiller is not running, the voltage readings are fairly constant; not more than 2-3V apart. Once the chiller is called, the...
  14. Run1on

    Current imbalance in three phase chiller motor

    One other item to mention: the controller for this chiller has display capabilities and as such we are able to watch the operating characteristics of the motor. The chiller's current draw is not consistent some of which can be due to load demands and possibly due to a load limiting functioning...
  15. Run1on

    Current imbalance in three phase chiller motor

    It is a school and we have found that another school within the grid of this utility has experienced similar problems.
  16. Run1on

    Current imbalance in three phase chiller motor

    Togel: The customer has lost their contactors once already. I will schedule a meeting with the local utility and request they meter their incoming supply for minimal requirements. This customer is at the end of the line and I suspect the KVAR generation of the utility is not sufficient to...
  17. Run1on

    Current imbalance in three phase chiller motor

    I have a current imbalance in a three phase chiller motor (480v 300 hp)Each phase: 1- 200 2 - 215 3 - 252. The voltage imbalance for this is less than three percent. We are also seeing other motors in the facility experiencing current imbalance. We also see the power factor readings for each leg...

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