T2 wiring with FIA Master switch

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Westfield 20XE
Posts: 9
Joined: Sat Feb 18, 2023 4:28 pm
ECU Model: No ECU
Distributor: QED motorsport

T2 wiring with FIA Master switch

Post by Westfield 20XE »

Evening all. I'm currently installing a T2 ECU on my Westfield with a FIA Master switch. I've connected the fused permanent 12v feed directly to the battery as per instructions from DTA but now I'm wondering if this would be better connected to the FIA Master switch on the side that when switch is off the supply will also be cut to the ECU or will it be okay just cutting the ignition supply to the ECU and leave the permanent 12v directly connected to battery??
stevieturbo
Posts: 3577
Joined: Tue Aug 02, 2011 12:08 pm
ECU Model: No ECU
Location: Norn Iron

Re: T2 wiring with FIA Master switch

Post by stevieturbo »

I guess it kinda depends if it is deemed just a kill switch, or battery isolator switch ?

Generally they tend to want the battery disconnected from the system, as well as ensuring the engine is killed. ( with suitable protective measures in place so as not to harm any electronics or alternator etc )

Either the battery ground, or positive would really need completely disconnected when the switch is activated.
katana
Posts: 455
Joined: Sun Jan 27, 2013 6:08 pm
ECU Model: S60 Pro
Firmware Version: 29

Re: T2 wiring with FIA Master switch

Post by katana »

Looking at the DTA wiring diagram, the 'always on' power supply is only for cooling fans and water pumps required to run after engine off, and in both cases everything is after the Master Switch, which implies to me, that DTA expect a FIA Master Switch to kill everything (at least related to DTA as far as they are concerned)
Westfield 20XE
Posts: 9
Joined: Sat Feb 18, 2023 4:28 pm
ECU Model: No ECU
Distributor: QED motorsport

Re: T2 wiring with FIA Master switch

Post by Westfield 20XE »

Thanks both of you for the confirmation. Yes agree completely about the cooling fan and the water pump which I don't have. On this basis I think I will reconfigure my setup and connect the perm 12v to the master switch then so everything will be isolated when the switch is turned off.

Thanks again for responding
Alex DTA
Posts: 1622
Joined: Fri Feb 28, 2014 1:03 pm
ECU Model: S40 Pro
Distributor: DTA
Firmware Version: 79

Re: T2 wiring with FIA Master switch

Post by Alex DTA »

katana wrote: Sun Feb 19, 2023 7:50 am Looking at the DTA wiring diagram, the 'always on' power supply is only for cooling fans and water pumps required to run after engine off, and in both cases everything is after the Master Switch, which implies to me, that DTA expect a FIA Master Switch to kill everything (at least related to DTA as far as they are concerned)
This is correct
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