Westinghouse WGen9500DF Auto-Start Wiring

12500 PEAK / 9500 RUNNING WATT DUAL FUEL • REMOTE ELECTRIC START  •  GENSTART BASE CONTROLLER
ACIDNI LLC  |  OCTOBER 2026  |  REV 1.0
YOUR INVERTER / TRANSFER SWITCH ANY 2-WIRE "GENERATOR START" DRY CONTACT GENERATOR START OUTPUT NO COM CONTACT CLOSED = start the generator CONTACT OPEN   = stop the generator WHITE BLACK GENSTART CONTROLLER BASE MODEL  •  WEATHERPROOF ENCLOSURE ALL CONNECTIONS ARE LABELED SCREW TERMINALS START SIGNAL IN SIGNAL COMMON GENERATOR START/STOP START/STOP 1 START/STOP 2 12V POWER IN BATTERY + BATTERY − GENERATOR RUNNING SENSE SENSE + SENSE − SETUP (on the GenStart web page) Start Mode: BUTTON  •  Double-Press: ON (3 sec) Arm 1 sec → wait 3 sec → start 1 sec WESTINGHOUSE WGen9500DF 9500W GAS / 8500W LPG • AUTO-CHOKE • 120/240V PUSH-BUTTON START/STOP lit button: red = armed, green = running its two wires TAP IN PARALLEL — DO NOT CUT ANYTHING GENERATOR 12V STARTING BATTERY + − install supplied 3A inline fuse on the + wire 5V USB ADAPTER + SENSE CABLE (SUPPLIED) + − plug the adapter into a 5-20R GFCI outlet L14-30R or 14-50R — 120/240V → TRANSFER SWITCH / INVERTER AC INPUT LEAVE THE GENERATOR SET UP LIKE THIS • Engine control switch — RUN (not STOP) • Fuel valve OPEN, fuel selector set • Oil level good, low-oil shutdown clear • Choke — automatic; 7-pin socket unused • Maintainer on the battery charge port 2-wire WHAT HAPPENS, STEP BY STEP 1. Your inverter or transfer switch    closes its start contact 2. GenStart waits the pre-start delay 3. Presses the button (1 sec) to arm —    the button lights red 4. Waits 3 sec, presses again — starts 5. The WGen9500DF makes up to 3 crank    attempts; GenStart waits 60 sec    for power, else reports a fault 6. Your inverter / transfer switch    opens the contact 7. After the stop delay, GenStart presses    the button — the generator stops The panel button and key fob keep working.

Connection Summary

GenStart TerminalConnects ToWire
START SIGNAL — SIGNALInverter / transfer switch generator-start output, NO terminalWhite, 22 AWG
START SIGNAL — COMMONInverter / transfer switch generator-start output, COM terminalBlack, 22 AWG
START/STOP 1One wire of the WGen9500DF push-button electric start (the lit START/STOP button) (tapped in parallel)Green, 18 AWG
START/STOP 2The other wire of the same button (tapped in parallel)Green, 18 AWG
BATTERY +WGen9500DF 12V starting battery, positive post or the + lead of its quick-connect plug — 3A inline fuse requiredRed, 18 AWG
BATTERY −WGen9500DF 12V starting battery, negative post or the − lead of its quick-connect plugBlack, 18 AWG
SENSE +Red (+) lead of the supplied USB sense cable, plugged into the supplied USB adapter in one of the 120V 5-20R GFCI duplex outlets on the generator panelUSB cable lead
SENSE −Black (−) lead of the same cableUSB cable lead
— (no GenStart terminal)L14-30R or 14-50R → your transfer switch / inverter AC input stays exactly as it is today. The 7-pin Smart Switch outlet is not usedExisting cable

Start Signal — Three Ways

OptionHow it worksUse it when
1. Dry contact (wired)A 2-wire contact wired to START SIGNAL IN (SIGNAL and COMMON): your inverter's or transfer switch's generator-start output, or the normally-closed contact of a relay whose coil is powered by utility power. Closed = run the generator, open = stop it.The inverter or transfer switch is close enough to run two small wires to GenStart. Available now.
2. WirelessThe Wireless Dry Contact Bridge Kit: a signal-source board at the inverter reads its contact and sends it by radio to the GenStart board at the generator, which then starts and stops the generator exactly as shown on this page.The inverter is too far from the generator to run the wire. Available now (the kit replaces the controller).
3. Utility power lossA second supplied 5V USB adapter plugs into an outlet powered by the utility, not by the generator. Wire its USB cable's red (+) lead to START SIGNAL IN SIGNAL and its black (−) lead to BATTERY − (ground). Do not use COMMON for this: on GenStart, COMMON is a +5V output, not ground, and wired there GenStart cannot see the outage. In GenStart's web page, open Settings > Start signal and set Start signal type to Utility power loss (5 V adapter). When the adapter's 5V is gone for the Start delay after loss (default 10 seconds, 1–600), GenStart starts the generator. Once utility has been back for the Stop delay after return (default 300 seconds, 0–7200; 0 keeps it running until you stop it), GenStart stops it.Backup for utility power through a transfer switch, with no separate relay. Available now in firmware 3.15.8. A GenStart uses one start signal: the inverter dry contact (option 1) or utility power loss, not both.
UTILITY POWER LOSS: Anything that removes power from the utility adapter looks like an outage to GenStart: unplugging it, a tripped breaker on its circuit, or a damaged or disconnected cable will start the generator. Plug it into a dedicated utility outlet that stays on and that the generator does not feed (if the generator powers that outlet, GenStart never sees the outage end). Use the start delay after loss to ride through short blips.

Settings — GenStart Web Page

SettingValue for the WGen9500DFWhy
Start ModeButtonThe WGen9500DF starts and stops from its lit panel push-button; its own controller sets the choke and runs the cranking
Double-Press Gap3 secondsThe first press arms the start module (the button lights), the second starts the automatic start sequence, the same behaviour as the Westinghouse WGen3600DFc and the Generac GP series
Press Length (Start)1 secondEach of the two presses is a firm 1-second press-and-release
Press Length (Stop)1.5 secondsA deliberate press stops the engine; the manual says to hold the button until it stops
Start Confirm Time60 secondsThe WGen9500DF makes up to three crank attempts on its own. GenStart waits for the running signal for the whole sequence and never presses during it
Retries1The generator already retries itself. If all three of its attempts fail (the button turns red), GenStart reports a fault instead of pressing again
Pre-Start Delay3 seconds (solar)
10–60 seconds (utility relay)		With a utility-loss transfer switch, a longer delay rides through short outages so they never reach the generator
Stop Delay (settle)5 seconds (solar)
5 minutes (utility relay)		How long the generator keeps running after the start signal clears. With a transfer switch the load has already gone back to utility, so this is an unloaded cooldown
Utility power loss (option 3)Start delay 10 s
Stop delay 300 s		With the utility power loss start signal, set these on the Start signal settings and leave Pre-Start Delay and Stop Delay at the solar values; the two sets of delays add together
⚠ CHECK YOUR PANEL FIRST: Stand at the generator and start it by hand with the button. If the first press arms it (the button lights) and the second press starts it, leave Double-Press ON at 3 seconds as shown. If one 1-second press starts it, turn Double-Press OFF. Then use GenStart's Test Run button and watch a full start, run and stop before you leave the system unattended.
ENGINE CONTROL SWITCH MUST STAY IN RUN: In STOP it disconnects the battery, and the button, the key fob and GenStart all stop working. Turning it to STOP is also the quickest way to abort a start or stop the engine by hand.
CHANGE THE FACTORY DEFAULTS: GenStart arrives with a 15-second start confirm time and 3 retries. On this generator that is too short: set 60 seconds and 1 retry before you connect the start signal, so GenStart never presses the button while the generator is still working through its own start attempts.
CARBON MONOXIDE: Run the generator outdoors only, far from doors, windows and vents, with a CO alarm in the building. GenStart never bypasses a generator's own protections; if the engine shuts itself down, GenStart reports a fault and waits for you.
TAP IN PARALLEL: The two START/STOP wires splice alongside the existing push-button wires (posi-taps or solder and heat-shrink). Nothing is cut, so the panel button and the wireless key fob still work normally.
NO OTHER CHANGES: Choke (automatic), ignition, fuel selector, the remote-start receiver and the 7-pin Smart Switch outlet stay factory. GenStart does not use the Smart Switch outlet, so a fault there does not affect it.
RUNNING SENSE — 5V USB, NO 120V INTO GENSTART: The supplied USB adapter plugs into a 120V outlet on the generator, and the supplied USB sense cable carries its 5V to SENSE + and −. It only has power while the generator is producing power, which is how GenStart knows the engine actually started; without it it cannot verify a start or retry a failed one. If your generator has its own USB port that is live only while the engine runs (check with a meter: 0V engine off, about 5V running), you can plug the USB sense cable into that instead and skip the adapter. Never wire 120V or 240V to any GenStart terminal.
BATTERY: The generator charges its battery while it runs. For a standby install, keep the included battery charger connected to the battery charge port.
PROPANE: If you run on LPG, the tank valve must be left open for unattended starting to work. On gasoline, leave the fuel valve open and keep the tank topped up.
SAFETY: Disconnect the generator battery before you begin wiring.
Start signal from your inverter
Start/stop button wires
12V battery power
Running sense (5V USB)
Generator power to your transfer switch / inverter
Negative / common
© 2026 Acidni LLC. All rights reserved.
GenStart™ is a product of Acidni LLC. This document is provided for use with genuine GenStart controllers and may not be reproduced or redistributed without written permission.
Westinghouse® and WGen9500DF are trademarks of their respective owners and are referenced here for compatibility identification only. Acidni LLC is not affiliated with, endorsed by, or sponsored by any generator manufacturer.
Installation involves low-voltage DC wiring only; nothing on GenStart connects to 120V. Follow all applicable electrical codes and the manufacturers' safety instructions. If you are unsure, hire a licensed electrician.
support@acidni.net  •  genstart.acidni.net  •  Rev 1.0 — October 2026