Electrical math help...lol

Okay I can't make my mind work this morning.
I want a momentary foot switch for my scroll saw, It draws 1.4 amps at 120v.
Lots of imports that are rated at 10 amps at 230 volts. Am I correct in assuming 10 amps at 230 volts will handle about 1/4 that power on 120 volts?
That's my thoughts from resistance loads, but since this involves contacts and I can't make my mind work, I'm wondering if I'm safe?
I want a momentary foot switch for my scroll saw, It draws 1.4 amps at 120v.
Lots of imports that are rated at 10 amps at 230 volts. Am I correct in assuming 10 amps at 230 volts will handle about 1/4 that power on 120 volts?
That's my thoughts from resistance loads, but since this involves contacts and I can't make my mind work, I'm wondering if I'm safe?
Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites, Midnite E-panel, Prosine 1800 and Exeltech 1100, 660 ah 24v ForkLift battery. Off grid for @16 of last 17 years. Assorted other systems, and to many panels in the closet to not do more...lol
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Main daytime system ~4kw panels into 2xMNClassic150 370ah 48v bank 2xOutback 3548 inverter 120v + 240v autotransformer
Night system ~1kw panels into 1xMNClassic150 700ah 12v bank morningstar 300w inverter
-Bill
Main daytime system ~4kw panels into 2xMNClassic150 370ah 48v bank 2xOutback 3548 inverter 120v + 240v autotransformer
Night system ~1kw panels into 1xMNClassic150 700ah 12v bank morningstar 300w inverter
22 AWG cable cannot safely carry 10 amps directly... The two questions are "what is the max continuous current" and what is the "branch circuit current rating"...
- 500 Watts / 240 VAC = 2.1 amps
If you run a 500 Watt inverter at 120 VAC:- 500 Watts / 120 VAC = 4.2 amps
So 120 vs 240 VAC are different questions if both are 500 Watt rated inverters.Then the question of what is the minimum wiring used on a 15/20 amp AC branch circuit... I have never seen any calculations, so this is a guess, but (for example) you have a 80 Watt power brick for your laptop, and find that it uses 18 (or even possibly 22) AWG cable on the 120/240 VAC input line.
From the NEC table, we see that they require 14 AWG for a 15 Amp circuit--But the fine print says that 14 AWG can carry 20 Amps (why the derating, I have never found out).
I believe the code issue is the ability of the small AWG cable to conduct enough fault current to trip the upstream protective device...
For example, if you can use 8 (insulated?) or 6 (bare?) AWG cable to ground bond a 200 amp service (I do not have an NEC book--numbers from vague memory decades ago)... From this chart, we find that:
https://www.powerstream.com/wire-fusing-currents.htm
8 AWG has ~473 amps of "fusing" current... (6 AWG fusing current for copper is ~668 amps).
I guess is that the cable needs to survive just "long enough" to trip the upstream breaker... If 8 AWG is OK for 200 Amp service (sake of argument, I do not have code to reference), then ~2x fusing current gives enough headroom to trip the upstream breaker/fuse.
22 AWG copper has a ~41.5 amp fusing current, or a little bit over 2x the 15/20 amp branch circuit you find in most home branch circuits (wiring, outlets, etc.). The 22 awg serving a 2.1 amp load is "safe" and OK to use on a 15 amp branch circuit (assuming GT inverter here) because if there is a short circuit somewhere, the 22 AWG wiring will conduct enough current to trip the upstream breaker/fuse.....
-Bill
The best method would be to use a motor rated relay with the foot pedal controlling the relay coil current only, this would prevent the foot pedal wiring from becoming a fuse.
Second system 1890W 3 × 300W No name brand poly, 3×330 Sunsolar Poly panels, Morningstar TS 60 PWM controller, no name 2000W inverter 400Ah LFP 24V nominal battery with Daly BMS, used for water pumping and day time air conditioning.
5Kw Yanmar clone single cylinder air cooled diesel generator for rare emergency charging and welding.
https://www.platt.com/platt-electric-supply/industrial-automation-controls/motor-starters-and-motor-contactors/search.aspx?q=well+pump+control+panel+240volt§ionid=5&groupid=69
|| Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
|| VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A
solar: http://tinyurl.com/LMR-Solar
gen: http://tinyurl.com/LMR-Lister ,
Off grid in Upper peninsula Michigan
I went with a different foot switch, still an import with same 10 amp, but the cord is roughly 18 gauge. Should be fine for the 120 watt scroll saw and my small shop vac (400 watt? 1 gallon)
Thanks for everyone's help!