AirConditioning / Honda 2000/ Progressive EMS...issues

Rbertalotto wrote:
Does humidity have any effect on the starting requirements of an AC unit?

Temperature. As one who has owned two EU2000i gensets and powered 13.5K A/Cs your results are exactly what I would expect ... as outside ambient temperature rises so too does compressor head pressure, causing it to draw even more power. With your EMS in the circuit and gensets running at ECO speed low voltage threshold is causing the EMS to disconnect power to the trailer, remove it and the A/C compressor starts even though long term damage may result from repeated excessive low voltage sag each time the compressor attempts to ramp up to speed. Your solution is to use both gensets paralled together in order to avoid excessive low voltage sag and to remove the EMS when running on the gensets.

Well the answer is clear,. TURN OFF ECO BOOST. The high heat increases the start current of the A/C. (Also the running current) I have proven this in personal testing of my A/C units, but that's another story.

Oh, and if you have not already done it, you might go topside in the early AM when it is still cook, Remove the covers and CLEAN the condenser coils.. That will improve A/C operation (If that is cleaning is needed) (That's also how I tested mine.. one of my 13.5 Amp A/Cs was tripping the 20 amp breaker,, Turned out to need a good cleaning,, once cleaned it was back to 13.5 Amps).

wa8yxm wrote:
Well the answer is clear,. TURN OFF ECO BOOST.

Disagree. Since the OP has already said his paralled EU2000i gensets will start his A/C just fine in ECO mode with his EMS removed but won't with it in the "clear answer" is to remove the EMS. :R

While removing the EMS may allow the units to start it will no longer protect the motors from a low voltage situation and cause pre-mature failure. Why have an EMS if you are going to remove it?

Why is the EMS shutting down? I am assuming it is because of a low voltage situation.

Turning off the Eco-Boost is the only option in the instance of a low voltage condition.

Because the Honda 2000 is not grounded I have never had my EMS on during its operation....so I am not sure how you have had it inline and on during operation of the one or two Honda's

Daryll

FLY 4 FUN wrote:
Because the Honda 2000 is not grounded I have never had my EMS on during its operation....so I am not sure how you have had it inline and on during operation of the one or two Honda's

Simple ...use a G-N bonding plug on one of the gensets' outputs and the EMS will happily pass power on to the trailer just fine. :B

If you don't want to make your own Progressive Industries offers this Generator Plug

Already did the neutral grounding plug modification . Thank for the replies

Rbertalotto wrote:
. . . Once it tries to start again, the PI-EMS unit trips and the compressor never comes back on until I go outside and shut off eco boost.

If I deactivate the EMS, then the AC will function with both generators on eco boost . . .

If the a/c unit has NEVER operated with the PI EMS activated (using a generator), chances are you need to use a ground/neutral bonding plug. However, it sounds like your a/c unit has operated successfully with the PI EMS under certain conditions.

FWIW, the PI EMS is designed to disconnect power when voltage drops below ~104 volts. However, it will allow voltage to drop down to 90-104 volts during compressor start (if less than ~500 ms in duration) without returning an error (or shutting down power). The PI EMS does need at least ~90 volts to simply operate. Less than ~85 volts and the PI EMS quits operating and the relay defaults to the open (no output) position. When voltage drops to 85-90 volts, typically the PI EMS relay starts to chatter loudly.

I believe the Dometic 475915 (a popular OEM unit) has an LRA of 63 amps. My experience has shown two Honda EU2000i's will not reliably start this particular a/c unit with the Eco mode on. Sometimes hard-start kits help, sometimes they do little.

Results powering 13.5k BTU a/c units with one or two EU2000i's vary widely. There are some folks who can start their 13.5k BTU a/c unit with one EU2000i. There are some folks who can't start their 13.5k BTU a/c with two EU2000i's paralleled with the Eco mode on. Why? Not all 13.5k BTU a/c units are created equal. In-rush current (LRA) can vary widely from one model to another. The a/c unit's inrush current needs (based on LRA) and the power source's (commercial or generator) ability to deliver sufficient inrush current to meet those needs determines whether a given a/c unit will start or not.

In many cases, a clamp-on inrush current ammeter can quickly isolate the source of the problem. Yes, voltage measurements are useful, but there are very few VM that can accurately read the those few ms of voltage sag during compressor start-up. That's why a good inrush current reading is so helpful.

Assuming you have no problems with a commercial power source, it's best to establish a good baseline by checking inrush current using commercial power while using a short 10-12 gauge extension cord. Once you've established this baseline, in the future it won't take long to isolate your start-up problems with the a/c unit, trailer wiring, RV extension cord, or generator.

otrfun wrote:
FWIW, the PI EMS is designed to disconnect power when voltage drops below 106 volts.

104 vac is the stated low voltage threshold for the Progressive EMS units. That said, I've found PI calibration could be better and reset my own EMS-HW30C against a known calibrated meter.

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