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Relay

Relay

(OP)
Ok, I just graduated with an Instrumentation Degree and got hired on as an I and E Designer.  I am working on a hydraulic schematic and trying to get some indicator lights wired off of a relay that is controlled by level switch or a temp switch.  How do I do this?  Keep in mind the voltage for the heater is 460AC while my control voltage will be 110AC

RE: Relay

What heater?  And where is the voltage that ancient 110Vac?  Do you mean 120Vac?

You need to be more specific and provide some more details.  You've only vaguely given a general idea of what you want.

Keith Cress
kcress - http://www.flaminsystems.com

RE: Relay

(OP)
My fault.  I gave you the wrong information.  I have a relay to be in series with a temp switch that is showing NC on the schematic.  After the relay coil, the circuit is completed meaning there are no more components.  I am trying to get this relay to switch on an indicator light when the temp switch is closed.  So i currently have my memory contact from my relay in series with the indicator, but these two components are in parallel with the relay and switch itself?  Did you get that?  Its all 120VAC   

RE: Relay

Upload the circuit diagram to engineering.com (Step 3 in the reply box). Your explanation of the circuit is terrible. No offence! smile

This should be simple enough when we see the schematic.
  

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If we learn from our mistakes I'm getting a great education!
 

RE: Relay

I would assume a simple relay, not a pollyphase relay.

RE: Relay

Two questions:
What's wrong with what you have?

Why do you need the relays? (Current level, rating of switch, other contacts are needed, etc.)

RE: Relay

(OP)
The relays are needed to control the indicators.  If you look above you will see a temp and level switch that act as a shut down switch before the actual start/stop station.  These are kinda the same thing, but they are another set of switches that control the indicator lights as far as for a warning.  I may be overthinking the schematic itself.  I just thing if the switches are tripped and opened, current wont pass through the memory contact thus not supplying the indicator lights with power.  Or am I actually overthinking myself?

RE: Relay

(OP)
Or will the fact that the switches open close the contacts, thus allowing current to flow through the indicator lights?

RE: Relay

Assuming the level and temperature switches are single pole devices, just wire each of them to switch a relay directly: just 110V AC, a relay, and a switch. Use as many relay contacts in as many locations as you need to switch lamps, interlocks, permissives, etc. Wire the lamp and a relay contact so it indicates the status of the switch, and wire a separate contact on the same relay into the coil circuit.
  

----------------------------------
  
If we learn from our mistakes I'm getting a great education!
 

RE: Relay

Okay I see your problem. The holding contact circuit should not be shunting out the relay itself. The holding contact should be in parallel with the switch. Then this parallel circuit would be in series with the relay. I've attached a schematic on a PDF. Take a look.

Eric Kench, P.E.

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