Generac Xfer Switch Holds On Down to 65% of Normal ??????

[richwaskowitz]

We had a sustained after hours brownout here a few months after I installed a Generac 20 kW with automatic xfer switch and the voltage was somewhere around 85/170 volts (out of 120/240). The xfer switch never dropped out and we lost an AC unit, a UPS and our mail server so I really got called onto the carpet by the IT dept. I went back and read the Generac docs and saw that it is set to drop out at 65% (78/156) !!! Isn't that crazy? I would have expected it to be much more sensitive than that or at least configurable. Now I need to add external undervoltage detection so that this never happens again. Have you seen this too?

 

[ceb58]

We had a sustained after hours brownout here a few months after I installed a Generac 20 kW with automatic xfer switch and the voltage was somewhere around 85/170 volts (out of 120/240). The xfer switch never dropped out and we lost an AC unit, a UPS and our mail server so I really got called onto the carpet by the IT dept. I went back and read the Generac docs and saw that it is set to drop out at 65% (78/156) !!! Isn't that crazy? I would have expected it to be much more sensitive than that or at least configurable. Now I need to add external undervoltage detection so that this never happens again. Have you seen this too?

What type ATS is it. The GTS switches have adjustable voltage drop and the HTS is adjustable with the genlink program.

 

[Joethemechanic]

I can't say I've worked on your transfer switch, but I've worked on a lot, and I can tell you everything had some way of setting voltage parameters for utility low voltage.

I think maybe what the literature is telling you are the factory settings, although they really sound low

 

[richwaskowitz]

It is a Generac RTSX2000A3 Nexus Smart Switch. I can find nothing in the documentation provided and Generac will not return my calls and I can't get anyone to answer the support line so I was hoping one of you have been in the same situation and have a suggestion.

I found a Siemens over/under voltage monitoring relay that will do what I need and provide me with a drop out setting range of 17 - 275 volts, adjustable hysteresis and time delays and I will probably install one of these to make up for the lack of such a feature in the switch. I just find it incomprehensible that the same features are not adjustable in this $700 switch.

 

[Joethemechanic]

$700 switch.

You know, as far as transfer switches go, that isn't much money. How big of a switch is this?

 

[iwire]

In my humble opinion Generac is the Kia / Yugo / LeCar of transfer switches and generators.

 

[ceb58]

It is a Generac RTSX2000A3 Nexus Smart Switch. I can find nothing in the documentation provided and Generac will not return my calls and I can't get anyone to answer the support line so I was hoping one of you have been in the same situation and have a suggestion.

I found a Siemens over/under voltage monitoring relay that will do what I need and provide me with a drop out setting range of 17 - 275 volts, adjustable hysteresis and time delays and I will probably install one of these to make up for the lack of such a feature in the switch. I just find it incomprehensible that the same features are not adjustable in this $700 switch.

The way it looks is the voltage drop out is adjustable. It is done in the controller in the generator.

 

[richwaskowitz]

NOT adjustable

NOT adjustable

On this model, the xfer switch has no smarts and is controlled by the gen. The drop-out and reconnect voltages are preset in the gen and are NOT adjustable. As hard as this may be for me to believe, it is true. I cannot understand why there are not many more issues out there with this gen like the one which bit me. I will have installed a proper over/under voltage relay in the line voltage sensing circuit and that will take of the problem. What is wrong with Generac that they would have a design like that?????