If you need a 40A contactor for a motor that just blew its starter, buy the Schneider LC1D32G7. Don't look for alternatives.
In my role coordinating electrical repairs for a mid-sized industrial equipment supplier, I've handled 200+ rush orders for contactors in the last three years. When a client calls on a Tuesday morning saying their production line is down and they need a replacement by Thursday, there's no time for analysis paralysis. For a 40A motor load—think a 15HP pump, a small conveyor, or a compressor—the LC1D32G7 is the part we stock. It's the one I order by default. And it's the one I'll explain why you should use, not just for compatibility, but for the time you'll save on installation and troubleshooting.
When I first started this job, I assumed the cheapest compatible contactor was the best choice. I'd compare specs for hours. Three emergency callbacks later, I realized total cost of ownership involves more than the part price—it's about the hours you burn wiring it in, the peace of mind from having clear documentation, and the hassle of replacements.
Why the LC1D32G7 Is My Go-To for 40A Jobs
The LC1D32G7 is a 3-pole contactor rated for 40A for AC-3 duty (motor switching). That's a key detail. A lot of contactors are rated at 40A for AC-1 duty (resistive loads), but for motors, that rating drops. The LC1D32G7 is specifically designed for the inductive load of a motor, which is what gives it a real-world 40A rating for 90% of standard industrial applications.
Here's what I like about it, from a practical standpoint:
- Coil clarity: The 'G7' suffix means it comes with a 110/120V 50/60Hz coil. That's the standard control voltage in the US. I've swapped dozens of mish-matched coils from other brands. This one, a 110V coil in a 40A contactor, is the right combo.
- Wiring convenience: The screw terminals are well-spaced. When you're in a hurry, you don't want to fight with a cramped connection point. (Should mention: we keep a handful of these on the shelf, pre-assembled with ring terminals.)
- Documentation is a lifesaver: Schneider publishes a datasheet and a wiring diagram that is actually readable. You can print the diagram, tape it to the panel door, and hand it to an apprentice. They won't call you with a dumb question.
The alternative—say, pulling a random 40A contactor from a generic supplier—might save you $15. But when you factor in the 30 minutes to decipher their manual, the risk of a mis-wired auxiliary contact, and the chance of the coil voltage being wrong, that $15 is a false economy.
"The value of a known part like the LC1D32G7 isn't just its technical specs—it's the certainty. Knowing exactly how it fits, what it connects to, and how to test it in 10 minutes.
How to Wire It: The Part That Saves You a Headache
A contactor is basically a big relay. An electromagnet (the coil) pulls the contacts closed to connect the motor to the power supply. For the LC1D32G7, the wiring is straightforward, but many people (including me, early on) get tripped up on the control circuit.
Here's the setup I use for a standard motor start:
- Power in (L1, L2, L3): The 3-phase line voltage (e.g., 480V) goes to the top terminals. Use a 20 amp multimeter (set to AC voltage) to verify you have 480V line-to-line between each pair—this checks your breaker and wiring before you connect the load.
- Motor out (T1, T2, T3): The motor leads connect to the bottom terminals. Ensure you have a 20 amp multimeter to check continuity on your motor leads before connecting.
- Coil (A1, A2): These are the low-voltage (110V) control circuit. A2 is typically the neutral. A1 gets switched through whatever relays or start/stop buttons you have.
- Auxiliary contacts (13-14, 23-24): I use these as a seal-in contact if I'm doing a standard three-wire start/stop. This is where a lot of people mess up: they don't use a normally open (N.O.) contact to hold the coil energized after the start button is released. Use 13-14 for this.
A quick trick: Before wiring the motor, close the contactor manually (by hand or by energizing the coil) and test the continuity across the contacts with your 20 amp multimeter. This verifies the contactor mechanism works. I learned this after a client wired up a dead contactor and thought it was their motor.
(Ugh—I should add: if you're working with an 800 amp circuit breaker feeding a main panel, do NOT test a contactor's continuity across that breaker's terminals. Test at the contactor itself, with the breaker off and locked out. Safety first.)
What to Do If the 40A Doesn't Fit Your Need
The LC1D32G7 is a 40A contactor for a motor load. It works for 80% of cases. Here's how to know if you're in the other 20%:
- Your motor pulls more than 40A FLA: Check the motor's nameplate for the full-load amps (FLA). If it's 35A+, the 40A contactor is fine. If it's 45A+, step up to a 50A contactor, like the LC1D50. Don't push a 40A contactor to its limit for a continuous duty 5HP motor that’s fully loaded.
- Your control voltage isn't 110V: The LC1D32G7 has a 110V coil. If your control system is 24V AC/DC, 230V, or 480V, you need a different coil. The 'G7' part is the coil code. You can buy the same contactor with a different code. (In March 2024, I had to swap a 110V coil for a 24V one for a client's PLC integration—took 10 minutes with a screwdriver.)
- You need a 4-pole contactor: This one is 3-pole. If you need to switch the neutral as well (uncommon for motor loads, but it happens), look at the LC1D09, etc.
- You're working with an 800 amp circuit breaker on a feeder: This contactor is for the motor branch circuit, not the main breaker. Do not confuse the two. The 800A breaker is for protection, the 40A contactor is for switching.
This was accurate as of Q1 2025. Schneider changes product codes sometimes, so verify the coil voltage and current rating against your motor nameplate before ordering. One final tip: if you're trying to understand what is contactor vs. a relay, the easiest way is to think of a contactor as a relay that can handle higher current—specifically, motor starting current. But that's a topic for another day.
I got this wiring diagram approach after a rush job in 2023 where we had to train a temp electrician in 20 minutes. The diagram was the only thing that saved us from a $50,000 production line halt. I keep a printed copy in every contactor kit now.
