Relay Switching Circuits; Energized ON or OFF?

[tictac]

I'm messing around with drawing up a simple relay circuit with LED indicator for an amp and I've noticed there's two ways this is being done in the schematics I've looked at:
1) Relay + LED Energized = ON
2) Relay OFF, LED ON or Relay ON LED off

In example 1 an LED/resistor network is placed across the relay coil so that when the - side of the relay is grounded (floating) both the coil and LED are energized, thus when the relay is activated the LED is ON.

In example 2 the relay coil and LED network are wired in series across the + and - (floating ground) of the power supply with the coil on the + side, followed by the LED/resistor then -. A switch is wired across the LED network so than when closed the coil is energized and the LED is OFF. Open the switch and the coil is de-energized and the LED is ON.

Any comments about advantages/ disadvantages to either circuit? Type 1 seems to be the most common; only disadvantage would be the coil and LED are on at the same time drawing more current then type 2. Current draw perhaps is so small it's not a factor....

TT

[Colossal]

Tictac,

I use #1 and an on-board LED as an indicator that the relay ON is on. Mostly as a convenience/sanity check for the builder. LED and relay are in parallel so when the player hits the front panel switch or footswitch, the circuit is closed and the LED and relay fire.

[tictac]

Thanks for that,

One reason I'm investigating this is I'm having a hard time getting my head around the Dumble ODS footswitching method. On the schematics I've seen it looks like the LEDs are in series with the relay coil with the relay coil corrected to the power supply and the LED circuit next. The ground end of the LED circuit is connected to an SPST switch which grounds the LED end of the circuit.

So you have PS - relay coil - resistor/LED - switch - ground

So having everthing in series like that works? Seems like the resistor would limit the current so that the coil won't close, NO?

TT

[Colossal]

So you have PS - relay coil - resistor/LED - switch - ground

So having everthing in series like that works? Seems like the resistor would limit the current so that the coil won't close, NO?

TT

Coil is in parallel with the LED. So it goes: 5VDC rail -> 150R/LED -> relay ->switch; where the 150R/LED are in series and they are in parallel with the relay. So both feed off the 5VDC source. I have done it with the LED in series with the coil, but had a couple of reports of the coil not firing. I recommend using one wire on a 5-pin DIN just to put 5VDC down to the footswitch. The footswitches themselves are then DPST so each footswitch indicator LED runs off that 5VDC source and the closure for the relay is the other half of the switch.

[tictac]

Thanks for the tips.... something else I just realized is you can combine both circuit 1 and 2 to make a dual LED status indicator. So Green can be clean and Red dirty. Not original I know but figuring it out for yourself makes it stick in the brain better,

thanks,

TT