The Compromise No One Talks About
For most OEM engineers, sensor selection happens fast. The bill of materials is already under scrutiny, the timeline is tight, and a flow switch from a distributor catalog ships quickly, fits a standard port, and clears design review.
But off-the-shelf sensors are engineered for the average application, not yours.
When your product is a medical laser, a specialty chiller, or a precision industrial printer, "average" becomes a liability. The hidden costs surface later: inconsistent trip points, pressure losses that force pump upgrades, material degradation, and assembly lines slowed by wiring workarounds.
This post breaks down exactly where those costs come from and what a custom-built sensor actually changes.
Problem 1 - Inconsistent Trip Points Cause Nuisance Shutdowns
What Goes Wrong
Off-the-shelf flow switches typically carry a ±20% tolerance on their set points. If your system requires actuation at exactly 1.5 GPM, a generic switch may trip anywhere between 1.2 and 1.8 GPM, a range that creates two distinct failure modes:
- False shutdowns the sensor trips before it should, halting the machine during normal operation
- Missed shutdowns the sensor hasn't reached its threshold, so the machine keeps running when it shouldn't
Both outcomes erode brand trust. Customers file service tickets. Field technicians replace components that aren't defective. Your support team absorbs the cost.
The Custom Fix
Every Thomas Products unit is bench-tested to your specific flow or level requirement before it ships. You define the set point; we verify it against that specification. The machine operates in its exact efficiency window, not within a 20% approximation of it.
Comparison graph showing ±20% trip-point tolerance in a generic flow switch versus a precision-calibrated actuation point at exactly 1.5 GPM in a Thomas Products custom unit
Problem 2 - Poor Flow Path Design Inflates System Costs
What Goes Wrong
Generic sensors accommodate a wide range of pipe sizes through internal adapters, steps, and transitions. Those features create turbulence inside the flow path and turbulence has a measurable consequence: elevated pressure drop (ΔP).
Higher ΔP means your pump works harder to maintain the same flow rate. Over the product's service life, that compounds into:
- A larger, more expensive pump in the original BOM
- Higher electrical draw per unit
- A bulkier overall product footprint
The Custom Fix
The Thomas Products Model 1100 is designed to integrate directly into your manifold or tubing geometry. By eliminating internal steps and transitions, the flow path stays streamlined, allowing a smaller pump, lower energy draw, and a more compact design.
Problem 3 - Default Materials Either Under-Perform or Overkill
What Goes Wrong
The off-the-shelf market defaults to two material choices: commodity plastic or standard brass. For specialty OEM applications, neither is typically right.
|
Scenario |
Risk |
|
Plastic housing in a chemically aggressive environment |
Degradation over time — often invisible until failure |
|
High-pressure stainless steel in a low-pressure medical path |
Unnecessary cost and weight for ratings never required |
The Custom Fix
Thomas Products works with OEM engineers to select the correct wetted material for each fluid, temperature, and chemical environment:
|
Material |
Best Suited For |
|
Monel |
Saltwater and marine environments |
|
PVC |
Fertilizers and mild acids |
|
Stainless Steel |
High-pressure industrial applications |
|
FDA-approved Polysulfone |
Medical-grade fluid paths |
The goal is material fitness, not a default spec applied to every application.
Flat-lay product photograph of Thomas Products sensor housings in Monel, Stainless Steel, Polysulfone, and PVC, each labeled with its target chemical or application environment
Problem 4 - Assembly Line Misfits Add Labor Cost at Scale
What Goes Wrong
Generic sensors rarely arrive ready for your line. Lead wires are the wrong length. Connector types don't match your harness. Mounting footprints require unplanned brackets. The result on the factory floor:
- Technicians looping and securing excess wire
- Adapters added that weren't in the original BOM
- Per-unit installation time that compounds across production runs
Small delays per unit become significant labor costs at volume.
The Custom Fix
The Thomas Products OEM program includes value-added assemblies shipped ready for your line:
- Exact lead-wire length specified by you
- Pre-terminated connectors (Deutsch, Amphenol, or your specified type)
- Pre-installed fittings matched to your process
The unit arrives ready to install, not ready to adapt.
The Real Cost Calculation
Before the next component review, run one quick calculation:
Minutes per unit adapting a generic sensor × production volume × labor rate = hidden sensor cost
In most cases, the delta between a generic part and a custom Thomas Products unit is smaller than that number and that's before accounting for field service calls, nuisance trips, or pump upgrades driven by pressure drop.
When a sensor is built for the machine, the machine performs the way the customer expects it to.
About Thomas Products & Industrial Control Solutions
Thomas Products, part of Industrial Control Solutions, specializes in the manufacture of flow switches, level switches, pump controls, sight window indicators, and Monel products. With over 40 years of industry leadership, the company prides itself on the diversity and quality of its product offering.
As a Service-Disabled Veteran-Owned Small Business, Industrial Control Solutions applies the same principles of military service to everyday practices: tireless dedication, rigorous standards of quality, and faithfulness to our values and mission. We can build and ship a sensor solution to your exact specifications, taking into account your application, media environment, and dozens of other variables to meet all your performance needs. Don't settle for a competitor solution with inferior versatility when we can exceed your expectations.
Thomas Products is ISO 9001:2015 Certified, giving our customers confidence that every product meets the highest standards of quality and rigorous testing requirements. Most importantly, we never lose sight of what the Industrial Control Solutions brand was built on: high-quality products and a deep commitment to customer service.
Check out our family of brands:
- Whitman Controls - Pressure switches, vacuum switches, differential pressure switches, temperature switches, and continuous level transmitters.
- Load Controls - Pump load controls, compact power sensors, fast-response load controllers, current sensors, and VFD solutions.
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Duro-Sense - Platinum and Noble Thermocouples, RTDs, and ISO 17025 Calibrated Wire Sales.
FAQs
Q: What is the main problem with using off-the-shelf sensors in OEM equipment?
A: Off-the-shelf sensors are built for average applications. For OEM products with tight performance requirements, this results in inconsistent trip points, mismatched materials, pressure drop penalties, and assembly inefficiencies, all of which increase total cost and reduce long-term reliability.
Q: What does "custom-calibrated set point" mean for a flow switch?
A: It means the switch is bench-tested and verified to actuate at your exact specified flow rate, for example, 1.5 GPM rather than within a generic ±20% tolerance band. Every Thomas Products unit is tested to your specification before it ships.
Q: How does sensor housing design affect pump sizing in an OEM system?
A: A poorly designed housing creates turbulence and pressure drop. Higher pressure drop requires a more powerful pump to maintain the same flow rate. A streamlined custom housing reduces that resistance, allowing a smaller pump selection and lower energy draw across the product's service life.
Q: What wetted materials does Thomas Products offer?
A: Options include Monel for saltwater and marine environments, PVC for fertilizers and mild acids, stainless steel for high-pressure industrial use, and FDA-approved Polysulfone for medical-grade fluid paths. Material selection is matched to your specific fluid, temperature, and chemical environment.
Q: Can Thomas Products customize lead-wire length and connector type?
A: Yes. Sensors can ship with your specified lead-wire length, pre-terminated connectors (including Deutsch and Amphenol), and pre-installed fittings, ready for your assembly line without modification.
