Power Equipment Forum banner
21 - 29 of 29 Posts

·
Registered
Joined
·
772 Posts
soft start is the way to go for sure!
I think one of the biggest takeaways from the above video for me is that he mentions hard start kits can appear to reduce inrush because the meter used to look at the inrush does not capture the true level of inrush. I had always thought that a hard start kit increased the inrush current, but after looking at several YT videos I changed my mind. Now I can see why those videos are misleading...they simply don't have (or are not using) the correct equipment. If the hard start kit shortens the startup time, then the meter may not respond appropriately to capture the peak inrush current and result in a false reading. Now I am back to believing that hard start kits are definitely not the solution for helping generators start large loads such as an A/C unit. I would agree that hard start kits do have useful applications in other instances.

The Micro-Air EasyStart controls startup current to both the run and start windings of the compressor...something that a hard start kit cannot do. Also, though he didn't go over it in the video (unless I missed it) the EasyStart unit allows the condenser fan to start first (because it is not wired to it) and then begins the startup (because of the short built-in delay) of the compressor. That also lightens the overall startup load that the gen sees.

This is a very telling graph from the above video...
Font Rectangle Slope Parallel Asphalt


And, he also provided the simplified wiring diagram for the EasyStart...something that I could not find on their website.

Organism Font Parallel Circle Handwriting
 

·
Registered
Joined
·
122 Posts
No doubt a soft starter is the way to go when running off-grid. I've heard there are 2 types of soft starts. One type ramps the voltage up at a set rate. The other type ramps the voltage up but uses feedback to adj the ramp rate if needed. Some feedback types monitor the speed and others monitor the current to make adjs.

In regards to the hard-start, I would like to see an O-scope screen capture using a voltage probe and a current probe simultaneously, before and after a hard-start installation.
 

·
Registered
Joined
·
480 Posts
I have used hard starts for years.
Better buy two when you get the first one, then plan to buy later.
The caps do not last long, and the lights start to blink again.
I am on my third set and have a spare on the shelf.
Useless as far as long life goes.
I am anxious to get my soft start unit.
 

·
Registered
Joined
·
122 Posts
This is not exactly what you are asking for, but it does have some interesting graphs and other data...

Nice article.
It makes me wonder how the hard start would compare to OEM with an older compressor that's pulling more amps due to age/wear.

Still a little skeptical about the prev video that stated most clamp-on ammeters miss the ~200msec current peak. That's a long time, at least in the direct measurement world. I have virtually no experience working on clamp-on meters but If they're actually missing a 200msec event, they must have really low sample rates.
 

·
Registered
Joined
·
772 Posts
I guess like everything else, there are cheap versions of ammeters and expensive versions. You get what you pay for.

In that article it compares the start current, start duration, and torque for the compressor using the OEM run capacitor only, adding a hard start cap, and then using the soft start. Very interesting data.

Rectangle Font Material property Parallel Pattern
 

·
Registered
Joined
·
29 Posts
Discussion Starter · #28 ·
Still a little skeptical about the prev video that stated most clamp-on ammeters miss the ~200msec current peak. That's a long time, at least in the direct measurement world. I have virtually no experience working on clamp-on meters but If they're actually missing a 200msec event, they must have really low sample rates.
I've worked on industrial sites, and I won't say what role I have but I work with electricians and instrument techs a lot. I have a nice quality $150 Greenlee multimeter, and I have found a few times that the more expensive Fluke multimeters that the instrument techs have get much better readings than mine when dealing with non-steady-state electrics. So how much worse would a no-name $40 clamp on meter perform?

Those videos are great, thanks for sharing them.
 

·
Registered
Joined
·
122 Posts
I've worked on industrial sites, and I won't say what role I have but I work with electricians and instrument techs a lot. I have a nice quality $150 Greenlee multimeter, and I have found a few times that the more expensive Fluke multimeters that the instrument techs have get much better readings than mine when dealing with non-steady-state electrics. So how much worse would a no-name $40 clamp on meter perform?

Those videos are great, thanks for sharing them.
No sure abt the cheaper clamp-on ammeters. Only experience I have the clamp-on meters is using Flukes. I build and repair direct connected DMM's among other instruments. Some designs use "sample and hold" circuitry which catches very short current pulses (in the usec range) however that adds complexity and expense. I suspect the cheaper clamp-on meters probably use periodic sampling and I have no idea what the sampling rate is. Tried looking for that info once but didn't find anything.
 
21 - 29 of 29 Posts
Top