(Not a pinball problem) I figured some of you guys would know how to do what I need to do.
1) I have a dual float switch which controls the level of fluid in a tank. The switch is two reed switches, one on top, one on bottom. (2 red wires top switch, 2 black wires bottom switch, 1 red and 1 black wire are tied together to power the circuit, the other red and black wire go to contactor coil terminals.
2) The switch opens and closes a 220v magnetic contactor, which runs a pump.

The problem is this, the wires coming out of the float switch are very thin, 22-24 gauge. The switch is only rated to 10W, 200V, 0.5A. The manufacturer says this: "Please Note : Float switch can not directly control solenoid valve or high power relay, AC contactor, etc. Small relays are required to transition."

What kind of relay are they talking about? I have it set up correct and it works just fine. I'm afraid that long term the wires will burn up or the reed switches will get overloaded.

#2 2 years ago

KOZ

KozMckPinball

Pinside member

7y 85,300 4,082 3

I think the manufacturer is stating that the switch cannot interface directly with 3 phase power. Most 3 phase power equipment use contactors instead of relays. The switch is wired to the control power side not the contact side.

#3 2 years ago

RFK

R8f1k

Pinside member

Grayslake, IL

10y 40,200 345 8 16

According to the manufacturer: "Please Note : Float switch can not directly control solenoid valve or high power relay, AC contactor, etc. Small relays are required to transition."

The picture you are showing is an AC contactor. I need to lower the power coming into the switch.

#4 2 years ago

DAY

Roamin

Pinside member

Saint-hyacinthe, QC

3y 29,050 365 1

You need to find out how nuch current is required to close your contactor. It should be indicated in the specs of the contactor. 0.5A should suffice though.. A normal coil that closes a contact should never pull as much a 0.5A, which is already more than a lot of devices will draw, let alone a tiny coil.

What they mean by a small relay is this : if your contactor pulls more than 0.5A, instead you need to use another relay, which would consume less than 0.5A to close it and then use that relay to switch a larger current, to then drive the contactor.

Float switch - > toggles small relay and use its contacts to send the proper voltage (with enough current) to the contactor -> contactor closes and can now drive high current for what you need.

Basically, the small relay is used so that it can drive higher currents needed to close the contactor.

#5 2 years ago

AXE

YeOldPinPlayer

Inactive member

Unknown

8y 111K 6,454 4 12

OP
Quoted from R8f1k:
Float switch can not directly control solenoid valve or high power relay, AC contactor, etc. Small relays are required to transition."

Something similar required when installing an aftermarket horn on a motorcycle. The horn button isn’t rated to carry the current needed so the button activates a relay, the relay activates the horn.

OP
Quoted from R8f1k:
2) The switch opens and closes a 220v magnetic contactor, which runs a pump.

Figure out how much current this device uses and use a relay that will handle that amount plus a safety margin. You may find out that “magnetic contactor” is another term for relay. Got a photo of that part? Any markings on it?

#6 2 years ago

RFK

R8f1k

Pinside member

Grayslake, IL

10y 40,200 345 8 16

Here are the specs on the float switch:
Max Switching Voltage : DC110V; Max Switching Power : 10W;

Here are the specs on the contactor:
3 pole, AC 220V, 27A capacity.

#7 2 years ago

AXE

YeOldPinPlayer

Inactive member

Unknown

8y 111K 6,454 4 12

OP
Quoted from R8f1k:
Here are the specs on the contactor:
3 pole, AC 220V, 27A capacity.

I searched DuckDuckGo for what is a magnetic contactor.
https://www.electgo.com/magnetic-contactor/
“Magnetic contactors are the same as the electrical relays”

#8 2 years ago

RFK

R8f1k

Pinside member

Grayslake, IL

10y 40,200 345 8 16

Quoted from YeOldPinPlayer:
I searched DuckDuckGo for what is a magnetic contactor.
https://www.electgo.com/magnetic-contactor/
“Magnetic contactors are the same as the electrical relays”

Yes, but the kind of contactor that I have is too high of a load for the switch. The company specifically states, that it cannot run an AC contactor.

#9 2 years ago

DAY

Roamin

Pinside member

Saint-hyacinthe, QC

3y 29,050 365 1

OP
Quoted from R8f1k:
Here are the specs on the float switch:
Max Switching Voltage : DC110V; Max Switching Power : 10W;
Here are the specs on the contactor:
3 pole, AC 220V, 27A capacity.

These are the specs of the contacts themselves. It means it can pass 27A in the contactor, but that doesn't say how much current it requires to physically close the contactor.

Are you feeding 220v in this contactor to switch it on? If so, you've already exceeded the specs of the float switch as it says it is DC and max of 110v.

#10 2 years ago

KOZ

KozMckPinball

Pinside member

7y 85,300 4,082 3

If it helps, this guy used DC reed switches to build a Chexx horn. He tapped off an existing 12V supply for the reed switch side of the relay, proper AC voltage on the other side of the relay.

https://pinside.com/pinball/forum/topic/super-chexx-goal-light-and-led-light-panel.

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