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  1. WWWJD

    Calculating VA and VAr from data sheets

    That'd be tough I think. You also have to consider that a motor is rated by its shaft power first, not it's electrical power. So your motor is rated for 180W shaft power. The motor's efficiency (and PF, voltage, actual load) will determine what your consumption numbers are going to be...
  2. WWWJD

    VFD Load Reactor / Ferrite Core Placement

    Peak voltages at the motor are due to the fact that you're sending a high frequency PWM signal along the motor leads. The motor leads have an associated inductance and capacitance value with them, depending on conductor type, length, insulation, etc. You have to think of motor leads in these...
  3. WWWJD

    VFD DC-Link Quick Disconnect?

    "Does the 40 HP drive drive a mechanical load or is it used only to regen back to the AC mains?" It's only there for regen back to the mains; more volume in the accumulator so to speak as I understand it. I'm kinda in the middle here; another guy spec'd all of this stuff out. So I can't...
  4. WWWJD

    VFD DC-Link Quick Disconnect?

    I'll provide a little clarity into the setup that I'm trying to glue together. What this is in a nutshell, is a dyno setup, using a set of regen drives (ABB 880 and ABB ACS 800). The setup is as follows: One 40HP ACS 800 regen drive fed from 480VAC, mounted to the wall. The DC Buss connection...
  5. WWWJD

    VFD DC-Link Quick Disconnect?

    All good points. Trying to prevent I.D.1.0.T. errors but I may inadvertently be inviting them in. Safest way would be to hard-wire everything in on the DC link side and force them into a position to where they need to bring the whole system offline prior to connection or disconnection...
  6. WWWJD

    VFD DC-Link Quick Disconnect?

    Hello all, We have a little project where we're tying ten 5HP 480VAC drives together on a common buss setup. These drives are on portable tables, and I'm wanting to find a way to do a quick disconnect on the DC connections. 1kV, 5-6A, 2 or 3 pole, finger safe on both the male and female side...
  7. WWWJD

    BACnet & PLC; question about typical BACnet object setup

    Hey fellers, Long time lurker, rare poster. [smile] I have a piece of equipment, PLC driven, which I recently upgraded with a BACnet gateway. I'm not extremely well versed in PLC programming; I'm even more of a BACnet virgin. My current PLC and HMI has a multi-state pushbutton linked to a...
  8. WWWJD

    VFD Input Power; Negative Power Factor on One Phase?

    Waross, This is a lab environment, where I'm trying to accurately measure the input power to a VFD that for lack of a better description, is on a dyno type load. I've looked into these meters a bit; the Hioki meter that I'm using is referred to as a 'demand' meter. I'm thinking that it's DSP...
  9. WWWJD

    VFD Input Power; Negative Power Factor on One Phase?

    Scotty, You're talking about PF displacement vs. distortion? There's no selection for that on this meter. I seem to remember a Fluke 434 I used years ago let you select between the two. It will let me toggle between THD fundamental and THD rms, but makes no difference in the readings, (I...
  10. WWWJD

    VFD Input Power; Negative Power Factor on One Phase?

    Hello all, I have something going on here that's really got me vexed. I have a 2HP VFD running on a 208/120 3Φ service, and I'm trying to measure input power with a power quality meter. One phase is reporting a negative power factor value, and I really have no idea why, unless this meter is...
  11. WWWJD

    3 phase plugs in Japan

    Hey guys, I'm having a hard time figuring out what kind of cord caps are used in Japan for their 200V poly-phase systems. On the wall, they use a type A (100V) like we used to use here in the states, but for 200V, I'm hitting a wall. Do they also use NEMA plugs? L15-20P, etc? I can't seem to...
  12. WWWJD

    Ammonium Nitrate and Aluminum; possible hazardous reaction?

    Hey guys, First off, let me apologize if this is the wrong place to post this question. I have ZERO experience regarding chemistry in general. I have a customer interested in a piece of equipment that is to be placed in an Ammonium Nitrate plant. This equipment is by weight mostly Aluminum...
  13. WWWJD

    Portable RS-485 / Modbus Master... hand held?

    Thanks guys; I'll give those a look. ~Mark
  14. WWWJD

    Portable RS-485 / Modbus Master... hand held?

    Hello all, I would like to find a small wall mounted / almost handheld GUI capable of controlling several VFDs via RS-485, without the need for PLC interface, etc. Just something small, simple. Does such a critter exist? Any alternatives I should consider? Thanks, ~Mark
  15. WWWJD

    GFCI required for an outdoor fan?

    I'm installing a 3/4 HP high speed blower on a mast under a canopy for cooling purposes. (fancy horse barn) Does that fan have to be installed on a GFCI circuit? I'm hard wiring this fan to a dedicated 20A circuit (no receptacle, no plug, just a wall switch). Everything I've found so far in...
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