What's new
What's new

5 HP American RPC upgrade with 15HP Idler, wont not turn on

Mr.JAJA

Aluminum
Joined
Jan 22, 2024
Location
Ramona CA
As the title says, I final got the 15HP idler connected to the existing 5 HP RPC as recommended, to get more stabile power for the equipment.

I installed the 15 HP idler with a separator relay, upgraded the feeding and output wires from AWG #12 to #6 and #8.
Now when I run the 5 HP idler as normal, I have L1-L2 = 237V, L1-L3 = 245V and L2-L3 = 257V on the output side. NO LOAD
The 15 HP idler is connected to this 3 legs switched with a contactor relay.
When I try to start the 15HP idler motor, wile the 5HP idler is running, it start turning, but don't makes it to the full RPM.
Only 50-60 RPM before the 50 Amp main fuse on the 1Ph input side turns of.
I have not connected any equipment yet. I have check the motor voltage (Y-Delta) and low voltage ( Y ) connection on the 15HP idler.
By the way, with the wire upgrade from #12 to #8 feeding the outlets, the Lathe starts faster and I can run at full speed 2800 RPM without tripping the Motor protector. (progress)

Please give me some input on the 15 HP, or did I wasted my time and $$$ on this?
Do I need a Starter capacitor on this?
Thank you for reading and give me your suggestion.
And have a nice Memorial -Day.

RPC 15HP.jpgRPC 5HP.jpg15HP motor 1.jpg
 
Yep, bring in start caps for a few seconds.

I automated my double motor units. A timer relay brings in the large second motor and its start caps after five or so seconds. Then a second timer drops the start caps after 2 or 3 seconds.
 
Yep, bring in start caps for a few seconds.

I automated my double motor units. A timer relay brings in the large second motor and its start caps after five or so seconds. Then a second timer drops the start caps after 2 or 3 seconds.
Do you have any capacitor size number?
Do I connect it via the timer between L1-L2? Or L1-L3?
Thanks for the help.
 
Update on my 15HP upgrade.
I still only can run the 5HP RPC. After installing a time relay and Capacitor (L1-L3). When the 5 HP RPC is running and I turn the 15 HP on, the Contactor relay makes a loud bussing noise and pulls on. The contacts for the capacitor are on the input side, there are contacts on the output side for the capacitor. The time relay is adjusted to 5 sec. and turns off after the delay time.
Do I need to go to the output side with the capacitor? I will give it a try tomorrow with some jumper wires.
Thanks for looking and giving me some guide's advice.
 
something wired wrong, impossible to diagnose from afar. Maybe my build threads will help.
 
Normal, I only need the 5 HP RPC. It has worked the last 20 years. 15 HP just sounds better. And who knows what comes next.
I will look at the contactor, as I remember the have sometimes helper contact build in. I might have it hooked up to a NC and when it is energized It will pull on/off with the power on. Good possible. Eyes are getting bad.
Thanks for the tip.
 
Ok,
Actually just had a nice smoke signal coming from the 15Hp setup.
Got it running without the humming noise after switching L2- L3. 15HP started nice and quiet. After 20 -30 seconds the capacitor got hot and blow oil out.
Found that the time relay is not switching either of the terminals.
The indicater LED work, not function on the contacts. 15-16-18 at all. So I sent it back.
 

Attachments

  • 20240603_094855.jpg
    20240603_094855.jpg
    962.3 KB · Views: 4
Yes, I know this for a long time. But every time, you learn something new. Check the function of each component before you install them. Now I wait for replacement parts.
 
The entire RPC was built for 5 Hp. The internal parts are going to as close to the line as possible if this RPC was built by a business.
Business sense to make as cheap as possible but make it work for a while....

List internal parts and ratings if you want.
 
OK, I looked and the 5HP RPC has a Telemecanique LC1DT20 installed. that's a low Amp relay for what I plan to do. For the 15HP idler I use a 40 Amp Contactor.
With all the connection on the "AMERICAN" 5HP I have to get the wire diagram and understand the connections. There are additional contacts on it. That means, I have to find a 40-60Amp with the same configuration.

Just for me to understand, The motor start CAP is only in for some Seconds from L1-L3 (dirty Leg), but the running CAP's are connected all time.(L1-L2 and L2-L3)

Why did the starter CAP blow up after 20-30 seconds running? It is a 270-324 uF 330 Volt, 50-60Hz
The 15HP idler was quiet and no load on any thing.
For now I will work with the 5HP only till I have found a solution and fixed the problems.
And I will write updates as I work on it.

Meanwhile I have to deal with a bigger Jaw-Neck surgery in the coming weeks.
 
.......................

Why did the starter CAP blow up after 20-30 seconds running? It is a 270-324 uF 330 Volt, 50-60Hz
.................................
Likely because it was NOT taken out of circuit as expected. Something failed to happen.

They have a short lifetime and are heavily overloaded. They survive only because they are used for a very short time. if they are left in-circuit, they rapidly overheat.
 
The motor start CAP is only in for some Seconds from L1-L3 (dirty Leg), but the running CAP's are connected all time.(L1-L2 and L2-L3)
A capacitor on L1-L2 is for power factor adjustment. Not a run cap.
Why did the starter CAP blow up after 20-30 seconds running? It is a 270-324 uF 330 Volt, 50-60Hz
If the white box (2nd pic, right side) is a potential relay. It did not drop the connection.
 
OK, looks like all is working now.
Got a new time relay, capacitor installed and test run it. 5HP RPC only running, no load 245-260Volt between all legs. Additional 15 HP running, 225-235Volt between all legs. No smoken timer kicks out after 2-3 seconds and 15HP idler runs smooth and quiet.
Let's make some chips now.
 








 
Back
Top