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Since you all seem to be contactor geniuses do you mind if I tag on a contactor question?

I have a situation where if one power supply fails - an separate / independent power supply must open as well. The logic is easy: power supply 2 Through a contactor's contacts and power supply 1 Powering the contactor coil.

But as any interruption in power supply 1 would rarely if ever occur - the contactor would be closed indefinitely under normal conditions.

The 40A (or less) load through the contactor contactor is a mix of resistance heating, lighting and small motors.

Given the above scenario; does there have to be anything special about the contactor? Or will a standard Honeywell 50A 3 pole contactor do the job indefinitely?
Good day PHM,

If the contactor is sized appropriately and is a quality brand product, then I think you will not have an issue. Contactor/Relays see their greatest electrical stresses when opening, as the load current simply wants to keep flowing via the very large electric field that are created just as the contacts begin to open. Once a contact is open wide enough ("wide enough" is based on the load's voltage) or is fully closed, the circuit will operate as intended as long as the contactor/relay is sized appropriate for the load current. The quality of the contactor/relay is also very important, as this will dictate the device's coil design and long term reliability. The coil is simple, but there are manufacturers that do cut corners and so may use thinner coil wire (which can self heat which can reduce longevity), or wire that is comprised of different materials (may not be all copper, but a mixture of metals). In most cases, contactors/relays lifetimes are rated based upon the number of open/close events... as the physical opening/closing of the contacts are mechanical and so do wear because of usage.

Depending upon the application, etc I would perhaps include a PS-2 feedback mechanism to indicate if the PS-2 is active or not... and implementing this would be trivial to do.

Cheers,

Sam
 
Thanks.

So far I've been using those physically huge Honeywell contractors with the interchangeable coils. R4234B 1062 To my knowledge they are no long being made but . . . . I had a row of them on the shelf. <g> But there are no more of the actual contactors and I only have one new 24V coil at this point. I could use a transformer for that one but I was really more curious what kind of service life I could expect overall from a constantly pulled-in contactor.

PHM
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Good day PHM,

If the contactor is sized appropriately and is a quality brand product, then I think you will not have an issue. Contactor/Relays see their greatest electrical stresses when opening, as the load current simply wants to keep flowing via the very large electric field that are created just as the contacts begin to open. Once a contact is open wide enough ("wide enough" is based on the load's voltage) or is fully closed, the circuit will operate as intended as long as the contactor/relay is sized appropriate for the load current. The quality of the contactor/relay is also very important, as this will dictate the device's coil design and long term reliability. The coil is simple, but there are manufacturers that do cut corners and so may use thinner coil wire (which can self heat which can reduce longevity), or wire that is comprised of different materials (may not be all copper, but a mixture of metals). In most cases, contactors/relays lifetimes are rated based upon the number of open/close events... as the physical opening/closing of the contacts are mechanical and so do wear because of usage.

Depending upon the application, etc I would perhaps include a PS-2 feedback mechanism to indicate if the PS-2 is active or not... and implementing this would be trivial to do.

Cheers,

Sam
 
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Thanks.

So far I've been using those physically huge Honeywell contractors with the interchangeable coils. R4234B 1062 To my knowledge they are no long being made but . . . . I had a row of them on the shelf. <g> But there are no more of the actual contactors and I only have one new 24V coil at this point. I could use a transformer for that one but I was really more curious what kind of service life I could expect overall from a constantly pulled-in contactor.

PHM
-------
Good day PHM,

Understood. The relay coil is simply a wire and so there is not a lot that can fail on it as long as the coil wire itself is suitably manufactured. Consequently, no real concern about having a relay switched on for extended periods/years assuming the environment it is in is suitable along with protection from physical damage.

Cheers,

Sam
 
Try Duck Duck Go - the cool-kids told me that's the way to go now. Nobody who is Anybody uses google anymore - it's So last-year.

BTW: Walmart sells that widget you want.

https://www.walmart.com/ip/Pelican-...3aacbe31eed3050d6906307ed09&gclid=aa5eb3aacbe31eed3050d6906307ed09&gclsrc=3p.ds

And here's the install guide -

https://www.pelicanwireless.com/wp-content/uploads/2021/08/PM5-120-240-InstallGuide.pdf


PHM
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https://www.pelicanwireless.com/power-control-module/

This is only a very small project.
Sorry didn’t read your post fully.
 
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We've used those big contactors in a can all by themselves here and there for outside lighting. Pulled in all day humming away no issues I'm aware of. That's our old way of doing things, most jobs these days have lighting panels it seems. I'm not aware of those things going bad, from the looks of them they seem similar to what you would see starting a compressor somewhere.

For a particular customer we partnered with Lutron and used their Vive line. Bunch of wireless equipment but the relay component is basically a RIB.
 
For a particular customer we partnered with Lutron and used their Vive line. Bunch of wireless equipment but the relay component is basically a RIB.
Dealing with the Quantum stuff. Its doesn't seem to be a product issue so much as a factory startup/programming that happens all remote. Not sure how you verify everything is wired correctly when you never step foot onsite. "As-built" drawings identical to the submittal set except a date change has been another issue. So these are my zone numbers? Yup. These fixtures all got redone in bulletin #40 and not reflected in these drawings wtf? Well that's our "as-builts" go off those...

Want to get their tech on-site, lol. Its 6-8 weeks out min and that's after a ton of hair pulling, kicking and screaming. The product might be good. Their internal people managing their projects absolutely suck.
 
For a particular customer we partnered with Lutron and used their Vive line. Bunch of wireless equipment but the relay component is basically a RIB.

Dealing with the Quantum stuff. Its doesn't seem to be a product issue so much as a factory startup/programming that happens all remote. Not sure how you verify everything is wired correctly when you never step foot onsite. "As-built" drawings identical to the submittal set except a date change has been another issue. So these are my zone numbers? Yup. These fixtures all got redone in bulletin #40 and not reflected in these drawings wtf? Well that's our "as-builts" go off those...

Want to get their tech on-site, lol. Its 6-8 weeks out min and that's after a ton of hair pulling, kicking and screaming. The product might be good. Their internal people managing their projects absolutely suck.
Good day All,

Sadly, virtually all the main stream lighting manufacturers use proprietary communications/protocols between their various components in order to maintain control (no pun intended) over the customer in terms of lock-in and pricing. Connectivity to the BMS or HVAC is simply an afterthought using a gateway (Bacnet) of sorts or a dry contact output (high tech, I know). Lutron and other systems could work very well, but long term commitment and support (even short term) is highly variable. Now, had these vendors offered components that used Industry standard protocols/interfaces between their various devices, then the designer or customer could pick and choose what devices best suit their needs and budgets + use whatever system they wanted as a front end and/or higher level control. However, this would create a far more competitive environment which these vendors have historically not been interested in doing... and so we have what we have

Cheers,

Sam
 
Discussion starter · #50 ·
Good day numbawunfela,

For direct lighting relay control, I would suggest going with the GE RR9 or equivalent (many vendors offer similar relays in the same form factor), as tickling these is very straightforward and requires little sophistication. GE relays last a very long time, as long as you do not pulse them too long, otherwise you will burn out the coil.

Depending on your base electrical enclosure and size, I can supply you with an insert with knockouts for these GE relays (you can source the relays from any supplier you wish along with your desired controller). I have custom inserts made all the time. For one offs, etc the cost + shipping may be more than your budget, but I put it out there if you cannot find any other option.

Cheers,

Sam
I have a post in the thread about AI...

After that fun little detour I have a few things baking. Thanks for the relay recommendation. Super helpful. I looked at the relay for around 2 seconds and saw the form factor was... odd and left it behind. I may need to revisit that.

I am off to renovate a chiller plant from Siemens Apology next week. I will try to post progress.
 
It could be the most open common candy corn stuff on the market. These systems we are required nothing more than supplying a handful of schedules, be it bacnet, modbus, hardwire, etc, the initial system as handed over to the owner is just a dog's breakfast. National account work,startup and program is from the OEM and its just a gigantic dumpster fire. They really don't give a crap about their end product.
 
It could be the most open common candy corn stuff on the market. These systems we are required nothing more than supplying a handful of schedules, be it bacnet, modbus, hardwire, etc, the initial system as handed over to the owner is just a dog's breakfast. National account work,startup and program is from the OEM and its just a gigantic dumpster fire. They really don't give a crap about their end product.

Good day orion242,

Agreed. Conceptually what is needed is not that complicated. I always find it amusing when I review various energy code requirements... and find that no one considers that the extra 5-10x more devices needed to meet the new codes all consume energy themselves... and so the net energy savings is not nearly as high as expected, sometimes worse than without the new stuff! The end goal is to minimize the environmental footprint and impact... and so adding more devices means more devices need to be manufactured, which consumes energy. More devices means less reliability and virtually all of these devices cannot be repaired when they crap out and so get land-filled... which creates more environmental issues. Those devices that are not land-filled, are sent somewhere (so more energy is used for transport) where environmental and labor laws are minimal and so even more impact to the environment, but also issues for those that have to deal with all the nasty stuff that the devices are made from. It is pretty crazy when one looks at the whole aspect pragmatically.

Cheers,

Sam
 
The end goal is to minimize the environmental footprint and impact... and so adding more devices means more devices need to be manufactured, which consumes energy.
The last encounter, where they didn't bother to take in account changes during the construction...

Two adjacent small rooms each had a controller and to be controlled independent. Well they changed to track lighting, these rooms where open ceiling and the walls didn't extend to the deck. So now its one circuit for both rooms. End result I have two controllers, the OEM flat out tells me both rooms are one zone but can't say which of the two controllers are actually controlling the circuit.

The fricken control was on/off, 8 zones. Lighting system just needed to follow the electrical panel schedule that has the zones called out by circuit. It couldn't be simpler and it was months of meetings and call backs. Lucky the call backs where the OEM and ECs problem to deal with. My time in emails and meetings, lifetime I'll never recover.

Duct static reset has been energy code forever in almost all 50 states. Its still not made boiler plate specs and no AHJ ever enforces it. I think the term is "green washing". Kinda like the shades of hydrogen lol or even electricity generation for that matter.
 
I have a post in the thread about AI...

After that fun little detour I have a few things baking. Thanks for the relay recommendation. Super helpful. I looked at the relay for around 2 seconds and saw the form factor was... odd and left it behind. I may need to revisit that.

I am off to renovate a chiller plant from Siemens Apology next week. I will try to post progress.
Good day numbawunfela,

Understood. The GE "style" of lighting relays may look odd, but are actually not that bad all things considered. They mount via a hole/knockout where one side is the LV control and other is the HV load switching. The knock out plate is mounted vertically against the base plate/insert and so creates a nice HV isolation barrier. Some vendors mount the relays in a single row side by side, others use two rows and stagger the top and bottom to provide easier access and visibility to the HV connections. There are other form factors as well, but these tend to be proprietary and so you are locked into a particular relay vendor. The Panasonic 2-wire relays have a metal foot with a springed clip and so are better and modern. However, you will have to create an isolation plate/barrier to accommodate unpopulated relay positions... whereas the GE style simply uses electrical knock out plugs and/or actual knockouts when no relay is present. Like most things, there are trade offs. The largest disadvantage with the GE style relays are the number of connections needed to control the relay (3 wires, so 3 terminals, plusgs, etc) and 2 more for relay status feedback. The feedback is not a true feedback, but a mechanical switch inside the relay and this switch can fail/break internally. The Panasonic relays are simply 2-wires that provide both the control and if driven and monitored appropriately provedes real time and true feedback showing one of 4 states (on, off, not present, fault). The Panasonic relays can be connected in parallel (up to 4) along with directly connecting the appropriate switches. This approach allows for the connected switch to control the relay without any involvement of the controller and provides real time feedback via two LEDs (green/red) of the relay(s) status. it is a very elegant and ingenious design. The negative is that the design to operate the Panasonic relay as intended is somewhat complicated and technically requires syncing of the control pulses to the zero crossing of the 24VAC waveform. One can hammer-fist control the relays with varying results in terms of operations and lifetimes... and many firms do this because they have not taken the time to understand how these devices work.

Cheers,

Sam
 
The GE "style" of lighting relays may look odd, but are actually not that bad all things considered. They mount via a hole/knockout where one side is the LV control and other is the HV load switching.
Think I know what you’re talking about. Can you shoot a link to a datasheet? LV side looks like a solenoid, fits 1/2 KO, HV terms on the opposite side? Yeah its some I/O, but its an easy interface and very popular.

If its what I’m thinking of, these are no big deal to interface with. Mounting is kinda a pain. They make divided wire trough though that with a good punch would make install reasonable and provide HV/LV separation.

The Panasonic relays are simply 2-wires that provide both the control and if driven and monitored appropriately provedes real time and true feedback showing one of 4 states (on, off, not present, fault)
Bit of a hassle to interface in the BMS market to say the least.
 
<snip>
I think the term is "green washing". Kinda like the shades of hydrogen lol or even electricity generation for that matter.
Good day Orion242,

Agreed. I have yet to see any inspector that has actually checked and certified a site that it is in full compliance of various Energy codes. When I asked the inspectors that do come to site, they look at me and shrug their shoulders. I am wondering if the Consultants purposely push the complexity of these codes in order to justify the lighting system costs or their fees?

I am all for energy efficiency, but I look at things pragmatically and from a variety of angles. I had one lighting project where the high level engineering firm spec'd out LED replacements for the customer, where the goal was to reduce energy. I looked at the name brand LED light and told the customer why would he install a LED light that consumed 20% more power than what he had??? Again, no real attention to details. Another project selected another name brand light... better specs... but had a 40% failure within 6 months of use. Yup, lots of energy savings there.

I had one project I did in 2018 that I am still very proud of that has yet to be outmatched by any of the lighting competitors to this day. The customer needed 48 high bay high brightness LED fixtures to replace old Halide versions. All of the off the shelf options were expensive and would require substantial rework for installation (electrical, mechanical attachment, area repairs, scaffolding installation, etc). The customer came to me and I designed a full custom LED retrofit replacement where the same module could be fitted into all four original fixture styles (pendant mount, recessed drywall ceiling, and two wall mount styles). Having reviewed the original fixtures I found that the interior light cavity loss was massive and so I could use LEDs with a bit lower lumen output, but still produce more resulting light (lux) where it was needed. The original lights consumed about 450W per fixture (400W for the bulb and 50W for the ballast... the still use non electronic ballasts for these)... mine consume a total of 18W... yes that is correct... 18W with the same light output as before... so a 96% energy reduction. However, my solution offered the following goodies:

1. No repairs or electrical/mechanical changes where needed
2. Reused original fixture housings and so leed points + no demolition or disposal costs
3. retrofit module could be installed using a scissor lift (most fixtures are 30' above actively used retail concourse levels), so no scaffolding
4. installation was done by 2 EC's after hours where all 48 were done over 4 evenings... so no downtime to the area
5. Module is fully dimmable and controllable both wired and wirelessly and can be connected to the BMS if desired (off the shelf options could not be dimmed or controlled directly via the BMS)
6. Module's max light output was 18000 lumens, but as I said, this amount of light was not needed and so they are programmed for less
7. Module included RGBW LEDs in addition to the main floor LEDs so that the lights can used for architectural, seasonal, or civic pride events
8. Module's design paid very strict attention to LED failure issues resulting in a statistical lifetime multiples longer than any off the shelf high bay
9. Module cost alone was about 1/3 less than off the shelf, but with more goodies + substantial savings given the reduced installation efforts and no repairs required.

I approached a number of the leading and notable engineering and architectual firms that specialize in Energy savings, etc and not one responded. I guess having maximum energy savings, having more features/functions, and saving customer's $ is not that important to them.

Attached is a pic of the module. Although the module looks simple, there are lot of tech goodies going on including using some quite advanced thermal dissipative materals. The latter is very important, as high brightness LEDs prematurely fail because of heat and so extraordinary efforts must be done to address the heat density. For example, these LEDs are spec'd to generate 135 degrees C (257F) on their surface and 90C (134F) on their case. At these temps they are spec'd to last 30000 hours. My design reduced the surface temp to 85C and a case temp to 58C which is dramtically less. Lowering the temp is key to LED longevity and by reducing these temps as much as I did, the LED lifetime will be significantly longer than the spec'd 30000 hours.

Yikes... I went off on a tangent... my apologies! As I said, I am very proud of the result and that after almost 6 years now of 24/7 operation they are still working as well as the first day + saving the customer about $800 a month on their power bill.

Cheers,

Sam
 

Attachments

I had one lighting project where the high level engineering firm spec'd out LED replacements for the customer, where the goal was to reduce energy. I looked at the name brand LED light and told the customer why would he install a LED light that consumed 20% more power than what he had?
I would be embarrassed beyond belief if I knew the total amount of "energy credits" outfits I have work for did working with some huge green outfits collecting state/fed rebates to install VFDs on motor that need to run at 100% 24/7. We install a VFD which at best maybe 95% eff, on a fricken motor than is on/off or equipment breaks. Somehow there is a rebate for this nonsense that make cents for multiple contractors to get involved.

Green washing...
 
Full disclosure, I work for Mircom on our OpenBAS product line so please delete if not allowed. Since there is posts about interfacing the Panasonic relays with a controller, this is an option.

We have a UL listed lighting controller that interfaces with 12 of these Panasonic relays. Controller and optional enclosure with deadfront are manufactured in Ontario Canada. 12x LED status, one RS485 port with BACnet/MSTP (slave only but discoverable), MODBUS/RTU and N2-Open out of the box.
 
Discussion starter · #60 ·
Full disclosure, I work for Mircom on our OpenBAS product line so please delete if not allowed. Since there is posts about interfacing the Panasonic relays with a controller, this is an option.

We have a UL listed lighting controller that interfaces with 12 of these Panasonic relays. Controller and optional enclosure with deadfront are manufactured in Ontario Canada. 12x LED status, one RS485 port with BACnet/MSTP (slave only but discoverable), MODBUS/RTU and N2-Open out of the box.
You may want to put your email in our profile so someone can find you if they like what you posted.

As a suggestion

Some hate on Canada
https://www.youtube.com/watch?v=4RHVoFpncgA

But we have some great forum members from there. :)
 
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