Hey, folks. I’m Paul with G&D chillers. I am the Engineering Manager here. Today, I wanted to take the opportunity to show you some of the functions and features of our ETL listed control panel on this two-stage chiller that we have here in our run station. This chiller is very similar to most of the chillers that we put out. It has many of the same components, the VFDs, the breakers, even the controller is the same. Of course, in this ETL listed control panel, we have a single point electrical connection so your electrician can land power in one place and all the other control wiring and motor wiring is already complete. That saves you money on the install and gives you a very reliable quality system. You have a control transformer up here, some breakers for those two control circuits. We also have a phase monitor. So that’s going to monitor all three phases of your incoming voltage, make sure it’s balanced. Make sure you don’t have any dips or spikes that could damage the chiller because it will actually shut it down and try to protect it. You have a VFD for the process pump so that it can pump at the rate that is required for your process and not waste extra energy running a pump full speed when it’s not required. We also have a VFD for the fan motors so that we can maintain very consistent head pressure. Refrigeration systems like to run very consistently without cycling fans and, of course, the pressure and temperature swings that that would cause. So that VFD is very helpful in that regard. Of course, you have various breakers and contactors as well. These two are for the compressors. This is for the chiller pump, which circulates internally. And then you have a breaker for some additional fans and the process pump as well. Now I want to get into how the controller operates. This controller has what we call a PID loop that is used to control temperature. So it can actually drive the temperature all the way to the set point rather than settling somewhere up above it where it matches the load. So it’s going to add capacity until it matches the set point and try to keep it there. You’ll see some very basic information here on the home screen. Of course, time and date, which would be used to timestamp any alarms that might occur. You have your current set point as well as your current pump pressure. The inlet, the outlet temperature, a very high level status level here. Right now, it’s off by alarm. There’s also off by DI. So if you turn off the switch on the control panel door, it would show that, compressor running. Those kind of details there. You can go in and turn your chiller on or off via the screen here or the switch on the door. If you arrow through these options here, there is, of course, a more detailed information screen or series of screens that shows information about the compressors and how they’re currently operating. And then you can go ahead and change your set point as well. It’s very simple. You just go in, arrow up or down, set it to whatever you’d like, and press enter to save it. There’s also, of course, the process pump pressure set point, so we can tell that VFD what pressure it needs to maintain to get the glycol out to your system. So we’re going to go through the information screen. There are four screens per circuit. This system has two circuits. It’s our GD-30H-2C. So, it has two fifteen-horsepower compressors. On the first screen here, you see your discharge pressure and condensing temperature that corresponds to that pressure. Since the system’s off, it’s matching the low side pressure. Otherwise, you would see something around two hundred to three hundred PSI generally. Down below, you have your suction pressure and your evaporation temperature. And then, of course, above that, you have the actual measured suction temperature. As a technician, you’d use that information to calculate your superheat, And you could do that here just by subtracting the evaporation temperature from the suction temperature, or you could go down two screens to take a look at the expansion valve screen, and it would do that for you. Since we’re off right now, it doesn’t show any sort of superheat, but it shows the set point of fourteen point nine degrees. That’s the superheat that we want to maintain and where the expansion valve is going to modulate and adjust to try and maintain that. You also see the percentage that the valve is open, as well as how many steps it’s open. So, of course, this is zero to one hundred percent, and then this is zero to, I believe, four hundred and twenty steps is the full open position. If you go down one more screen, you see your set condensing temperature that the fan is trying to achieve. Right now, it’s a hundred and thirteen degrees since it’s off. But once the system starts up, it’s going to gradually reduce that, to get as much cooling effect from those fans as possible and lower that condensing pressure to increase your efficiency and capacity. There’s a very high-level status screen for the compressor as well. Right now, it’s an alarm, but you might see that it’s running, or that it’s shutting down, and there might be a countdown timer shown as well. So, if it just starts up, there’s a minimum run time that it should stay on. That’s to protect your compressor and get the maximum life out of it. So it’ll display that countdown timer to the right and the same thing when it shuts off. You want it to stay off for a certain amount of time before restarting it. As you go down here, you’ll see that now we’re at circuit two. It shows the exact same information on the next three screens that we just looked at for circuit one. You can see a graphic here on the very final screen of this information screen. It shows both entering and leaving temperatures of the heat exchanger or evaporator in this machine. It also shows the status of the flow switch and the pump. So, if you have the pump running and no flow, it’s going to show that. Of course, you’ll have an alarm as well. It’ll also show the request percentage that the PID loop is generating to tell this chiller how much compressor to run. So, we’ve shown you the controller. That’s when you have this control panel open. A lot of times, you won’t have it open, though, and you’ll want to turn your chiller off or on. Of course, we have three switches on the outside of this chiller. One is the control power, and that will, of course, instantly shut down your chiller if you need to do that in an emergency situation. Most of the time, though, you’ll just leave that on even if you do want to have your chiller off, because that leaves the crankcase heater energized, so that you’re ready to start when you do need your chiller. You’ve got a keyed switch. The key, of course, is removable in any position so that you can lock out those switches and you don’t have anyone messing with your, with your chiller here, turning it off when you don’t want it off, or on when you don’t want it on. There’s a switch for the chiller start stop. Right now, it’s in the stop position. You can turn it to the start position. Same thing for the process pump. Of course, we don’t have anything enabled right now, so you didn’t hear anything start up, but that is how you would operate your chiller. Hope that was helpful for you guys. Of course, if you have any questions, please do feel free to give us a call or shoot us an email. We’re available anytime. Contact Us