Trying to decide on an EMS

Cmprman

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Which one is best?
 
That bulldog lights up bright. It also does not have a cover to keep rain and water out of the electrical connection.

Ray
 
As mentioned above, the dog does shine bright, but it keeps me from tripping on the power cord if I have to do something like dump a tank at night. I also like having bluetooth so I can see power status and consumption in realtime, and has the EPO feature.

The Progressive does not appear to have bluetooth or EPO if those are important to you.
 
EPO just means it will disconnect the power feed given a set of parameters is out of range. The Progressive does this as well. That is really what these mean by "EMS," given they really don't actually manage anything. I have owned the shown 50amp version and now have the hardwired version. Don't know if it has ever saved anything yet, but I don't view that as a bad thing.
 
I like the Watchdog for the features and the light. I also like that the surge protect part is user replaceable if it sacrifices itself to protect. Have used Hughes products for years and have not been disappointed.
 
The Joules rating is not the same on those two. I'd opt for the one with the higher rating.

Bob
But how many joules are enough? 2,000? 3,000? 40,000? This is a bragging number that really doesn't matter in real life. None of these units will prevent a direct lightning strike, which is about the only time your RV will ever see anywhere near this energy level.
 
As mentioned above, the dog does shine bright, but it keeps me from tripping on the power cord if I have to do something like dump a tank at night. I also like having bluetooth so I can see power status and consumption in realtime, and has the EPO feature.

The Progressive does not appear to have bluetooth or EPO if those are important to you.
What is EPO?
 
NJKris said:
What is EPO?

Hughes marketing term for Emergency Power Off, killing the power automatically.

From the EMS-PT50X manual, one section:

Low Voltage Protection: Whenever the AC line voltage drops below 104V for longer than 6 seconds, the EMS will automatically shut down power to the RV

So Progressive Industries has "EPO" but they call it "EMS". In contrast, Hughes does not have "EMS" capability. :)


I used to think I'd like a Hughes for the Bluetooth data displays but then I read a lot of issues due to their "feature creep".

Hughes added an overcurrent protection that kills the power as soon as the current (amps) exceeds the device's rating, whether it's 30 amp or 50 amp.

In other words, the thing thinks it's a circuit breaker.

People were reporting that as they approached the pedestal limit, any brief spike in the current caused the Hughes to kill the power, even when the duration was not long enough to trip the pedestal breaker.

I looked at their app to see if that "I'm a circuit breaker" nonsense could be shut off but no. So they are no longer of interest to me.

Progressive Industries and others did a similar thing when they decided to trip when the line frequency was too far away from 60 hertz. That never happens in real life on the commercial grid nor is it a significant concern even if it did.

But noisy lighting on the same circuit imparted electrical noise on to the wiring and PI units experienced nuisance power shutdowns because they thought there was a problem with the frequency. They seem to have fixed that with better filtering but still. But why have it other than as a sales differentator?

Ray
 
darrellr said:
But how many joules are enough? 2,000? 3,000? 40,000? This is a bragging number that really doesn't matter in real life. None of these units will prevent a direct lightning strike, which is about the only time your RV will ever see anywhere near this energy level.

Exactly correct. There is so much surge suppression built into the grid, and into many appliances, that this is just a marketing gimmick.

Ray
 
Hughes marketing term for Emergency Power Off, killing the power automatically.

From the EMS-PT50X manual, one section:

Low Voltage Protection: Whenever the AC line voltage drops below 104V for longer than 6 seconds, the EMS will automatically shut down power to the RV

So Progressive Industries has "EPO" but they call it "EMS". In contrast, Hughes does not have "EMS" capability. :)


I used to think I'd like a Hughes for the Bluetooth data displays but then I read a lot of issues due to their "feature creep".

Hughes added an overcurrent protection that kills the power as soon as the current (amps) exceeds the device's rating, whether it's 30 amp or 50 amp.

In other words, the thing thinks it's a circuit breaker.

People were reporting that as they approached the pedestal limit, any brief spike in the current caused the Hughes to kill the power, even when the duration was not long enough to trip the pedestal breaker.

I looked at their app to see if that "I'm a circuit breaker" nonsense could be shut off but no. So they are no longer of interest to me.

Progressive Industries and others did a similar thing when they decided to trip when the line frequency was too far away from 60 hertz. That never happens in real life on the commercial grid nor is it a significant concern even if it did.

But noisy lighting on the same circuit imparted electrical noise on to the wiring and PI units experienced nuisance power shutdowns because they thought there was a problem with the frequency. They seem to have fixed that with better filtering but still. But why have it other than as a sales differentator?

Ray
Thanks. Darrel, sorry, missed your post somehow.
 
People were reporting that as they approached the pedestal limit, any brief spike in the current caused the Hughes to kill the power, even when the duration was not long enough to trip the pedestal breaker.

I looked at their app to see if that "I'm a circuit breaker" nonsense could be shut off but no. So they are no longer of interest to me.

This is a good reason I would not buy the Hughes. A circuit breaker can hold 110-125% of load for a quite a while. Camping on a 30A site its not to hard to hit 29-31A for brief periods. I'd prefer the CB do its job.

Actually I'd like to be able to control the parameters like over/under voltage, duration,.... but no one allows that.

Jim M.
 
X2.Consider the hardwired (onboard) version.

I have owned the shown 50amp version and now have the hardwired version. Don't know if it has ever saved anything yet, but I don't view that as a bad thing.

X3
Hardwired with the display. It is interesting to see what current you are using from inside your camper.
Mine has tripped two or three times with low voltage error. 30 amp version.
 
September will mark the 10th anniversary of my installing my [FONT=&quot]EMS-HW50C from Progressive Industries.[/FONT]
[FONT=&quot]It has tripped [/FONT][FONT=&quot]several times over the years. It shut off power several times in one night at a COE park in southern Oklahoma. I used my multimeter and determined the incoming voltage was 138vAC. The park was shut down the next morning. Rising lake water had gotten into some power equipment.[/FONT]
[FONT=&quot]
[/FONT]

[FONT=&quot]My unit doesn't have/need a light since it's hardwired and out of sight.
[/FONT]

[FONT=&quot] [/FONT]
 
I like the Watchdog.

I have the 30a model.

It has Bluetooth. One time it shut off because of amperage & I was able to turn it back on from my smartphone.
 
I wonder at the folks who say a surge protector isn't needed, that it's built into the grid, that undervoltage or overcurrent or miswiring at the pedestal aren't a good reason to kill power. That can kill appliances or even people.

I have worked with both high and low voltage electricity all my life. And I've had quite a few appliances fried by surges in the past. For a few hundred bucks and the temporary inconvenience of maybe getting my power shut off automatically I'll take that any day over the damage it could prevent.

And to the naysayers, yes, I realize it can't prevent everything, but it prevents a lot. Mine is a Hughes btw and I'm happy with it.
 
I have a good quality surge protector and I believe that is all that is needed. Specifically, one that displays the status of and at the power post, i.e. open neutral, open ground, reversed line and neutral, etc. I have my voltage and current monitoring system that is easily visible inside our TT.

As to surviving a direct lightning strike to the power post or your RV, you will know it occurred as there will be only a pile of ashes on your RV site. A surge protector or EMS won't make any difference other than add a bit to the fire.

Many power surges are the result of nearby lightning strikes inducing voltage on the primary side of the power line. The power company has protection for this event but sometimes the protection devices are some distance from the power distribution point. Nominal power distribution primary voltages are 7.2kV single phase and 12.5kV three phase. The picture is a typical power distribution system with surge protection.

If one doesn't understand electricity or lightning, then buy an EMS so you will feel good about it. Expect to spend $250 to $500.

Bob
 

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