early this morning around 1 am got a high chilled loop alarm on my phone ( I installed a number of wireless temp sensors). Since I was sleeping on my boat next slip, I got up and went on the 110 to check it out. found a nasty electrical burn smell in the ER and found this melted terminal block in the Cruisair control panel. Immediately shut down the two Air Con breakers in the main panel. My AC tech came this morning and bypassed the block but we have two fried chiller control boards… running on one chiller till we get the new ones glad I had the alarm set up, damage would have been worst without it.
Any idea what caused the meltdown? Seems like you are pretty diligent in checking for loose connections and such. So wondering why this would happen?
Melt down at the black lead in. The gauge of that internal conductor looks pretty small, near toaster element sized. No where near the capability of the supply cable. So, what amp rating was that Din connect supposed to be rated at? What worse case current could the chiller draw? I have also caught my self capturing the cable insulation in to far on these type wire clamps. It is hard to get a feel or visual when making wire connects of these din blocks and other bare wire capture devices. I do prefer a lug or crimp on terminal strips or post, over these. Next, I wonder how many other captive wire clamps could be loose? Kill all the ACv and tighten down all those wire clamps. Could take a while but after a few, you will have an idea to continue or feel confidant that all are tight. Lets all take a breath, close our eyes and pray for goodness. That could of turned into a real ugly fire..
The next one had a couple of slightly loose connections. We checked them all. Yes I was surprised to see how thin the conductor is inside. Each chiller pulls about 30 amps. No start up surge as they re on freq drives. I never liked how that crusair box only has two inlets for 3 chillers and the pumps only so much that can be inspected on a regular basis. i think my cheap temp sensors paid for themselves today If I hadn’t gotten the alert about the chilled loop being above normal, it would have continued melting for a while…
When you have free time, pull the heavy cables from the right of the meltdown and clean the terminals, and the clamps. You've got some resistive heat going on there. I was reading another thread and galvanic isolators came up in some posts. May want to see if you have one, and if it's working. Stray current in the marina can come from weird places. There was a guy killed in Galveston at a marina a while back when he was in the water working on a boat and someone nearby was electrifying the dock. Glad you caught it now.
We checked the other block and wires. They re fine No worry about galvanic corrosion. We running on 480v shore with an Atlas system.
I m using MOCREO sensors. Wireless, built in rechargeable batteries, communicate with a hub which in turn connects to the boat WiFi. i have sensors on the loop, each 3 coils of the 3 chillers as well as sensors in the freezers. Not real time, there can be a 1 to 3 minutes delay. they re on Amazon, search for MOCREO I also have a MySpool sensors for power failures. They also make water sensor for leaks.
My home insurance provided a TING system from Whisker Labs with a limited time (2 years? I forgot) subscription. The device monitors the electrical system and flags electrical disturbances caused by arcing. The device plugs into any electrical outlet and is set to the home WiFi to communicate with HQ. It apparently alarms via messages from the administration, but otherwise it provides weekly power quality reports and voltage fluctuation graphs. Here's a sample: There's also a news section that showcases the "save" of the week where an incipient problem was flagged and an electrician responded and saved the day before power loss or fire loss occurred. I didn't know anything about it until State Farm offered it for free, and didn't really think it would be a "thing" for my house, as it's fairly new and the electrical system appears to be un-molested by amateurs, but, it's free, so went for it. Pretty impressive. I'm guessing the voltage dips are when the heat pump kicks in, as it doesn't have inverter starting. It reports power blackouts, brownouts, and WiFi outages. I've seen plenty of arc-damaged electrical connections on yachts and wondered if the system would work there, since the marina environment could maybe be very electrically "noisy". I have no relationship with the product other than as a passive user.
Update I hate Cruisair and the evil empire known as Dometic turns out they no longer carry the boards as they have switched to fully integrated and computerized control units…. All eggs in one basket, no redundancy my air con tech had one spare board and control panel in his warehouse so we ve been running on two chillers. He also found two used one from a buddy of his so we should be able to get the third chiller running in the next couple of days. This Dometic BS reminds me of Sea Recovery having discontinued their touch screen and replaced by a different one which required a new motherboard and bypass valve… $6000 10 years ago. long term solution maybe to switch to Marine Air control boards…. Or maybe we can get a Flagship style chiller control with just basic relays and LEDs diagnostic instead of that computerized crap.
I see no difficulty in just purchasing the controls (furniture, power supply, relays & thermostat) from flagship or like re-sellers. Everybody uses the same compressors, pumps and fans. Using your past favorite phrase; You don't have to BOAT. Oh Sorry, Bend Over And Take-it Dumbetic continues to install headaches.
I know. I don’t want to deal with any overly computerized controls. I need to pull the wiring diagram for my flagship chillers but it seems to me that using one relay for each safety circuit (low pressure, high pressure, loop flow, loop freeze) would be able to shut down the main compressor relay in case of a fault. I ll have to see if the switches are normally open or closed but in any case the second pole of each relay could be used to trigger an LED for troubleshooting. doesn’t seem to be rocket science…
I checked my flagship chillers, they use 4 lock out relays (made in the USA) to shutdown the compressor, turn on a diagnostic LED. The lock out design prevents the compressor from restarting over and over after a shut down and pressure comes back down
