MKCM OIL SIGNAL flow switches combine an electrical low-flow signal with a visible float in the standard transparent tube. The switch is set for the specified oil and operating flow before shipment. A CAC902 protective cover surrounds the sensing assembly, and OFF and ON contact versions are listed separately for every port size.
Construction and operating specifications
| Parameter | Specification |
|---|---|
| Fluid | Oil |
| Maximum temperature | 60°C |
| Pressure resistance | 1 MPa |
| Standard connection | Rc female thread; R male or mixed connections available on request |
| Maximum operating voltage | 300 V AC/DC |
| Maximum operating current | 0.5 A AC/DC |
| Contact capacity | 50 VA |
| Switch setting | Fixed at shipment; specify oil and required operating flow |
| Flow tube | Acrylic, standard version |
| Protective cover | CAC902 |
| Fittings | C3604 brass; SUS construction can be requested |
| Spring | SUS304 |
| Magnetic float | Aluminum |
| O-ring | Nitrile rubber, standard version |
| Lead length | 200 mm standard; other length or cabtyre cord on request |
| Heat-resistant option | Up to 100°C; brass tube and fluororubber seal |
| Pressure-resistant option | Up to 5 MPa; brass tube and fluororubber seal |
| Visibility of special versions | Float cannot be visually inspected in the brass-tube versions |
Switching principle and contact selection
A magnetic float and reed switch produce an electrical contact change when oil flow passes the specified threshold. Choose the OFF version when the contact must open as flow decreases, or the ON version when the contact must close as flow decreases. Keep the complete suffix in the order and wiring documentation. The selected operating flow is fixed at shipment and cannot be changed later. The table’s setpoint-selection range and maximum line-flow value are different quantities: a maximum flow of 50 L/min does not mean that a 50 L/min switch threshold is available.
Models and dimensions
| Model | Port | Length (mm) | Width (mm) | Depth (mm) | Minimum bore (mm) | Factory setpoint selection range (L/min) | Maximum flow (L/min) |
|---|---|---|---|---|---|---|---|
| MKCM20-1TL-OFF | Rc1/8 | 80 | 30 | 22 | 6.5 | 0.005 (5cc) to 2 | 5 |
| MKCM20-1TL-ON | Rc1/8 | 80 | 30 | 22 | 6.5 | 0.005 (5cc) to 2 | 5 |
| MKCM20-2TL-OFF | Rc1/4 | 80 | 30 | 22 | 6.5 | 0.005 (5cc) to 2 | 5 |
| MKCM20-2TL-ON | Rc1/4 | 80 | 30 | 22 | 6.5 | 0.005 (5cc) to 2 | 5 |
| MKCM20-3TL-OFF | Rc3/8 | 86 | 30 | 25 | 6.5 | 0.005 (5cc) to 2 | 5 |
| MKCM20-3TL-ON | Rc3/8 | 86 | 30 | 25 | 6.5 | 0.005 (5cc) to 2 | 5 |
| MKCM30-2TL-OFF | Rc1/4 | 100 | 44 | 32 | 9.5 | 0.05 (50cc) to 5 | 10 |
| MKCM30-2TL-ON | Rc1/4 | 100 | 44 | 32 | 9.5 | 0.05 (50cc) to 5 | 10 |
| MKCM30-3TL-OFF | Rc3/8 | 104 | 44 | 32 | 9.5 | 0.05 (50cc) to 5 | 10 |
| MKCM30-3TL-ON | Rc3/8 | 104 | 44 | 32 | 9.5 | 0.05 (50cc) to 5 | 10 |
| MKCM30-4TL-OFF | Rc1/2 | 110 | 44 | 32 | 9.5 | 0.05 (50cc) to 5 | 10 |
| MKCM30-4TL-ON | Rc1/2 | 110 | 44 | 32 | 9.5 | 0.05 (50cc) to 5 | 10 |
| MKCM35-4TL-OFF | Rc1/2 | 124 | 49 | 44 | 13.5 | 1 to 10 | 25 |
| MKCM35-4TL-ON | Rc1/2 | 124 | 49 | 44 | 13.5 | 1 to 10 | 25 |
| MKCM35-6TL-OFF | Rc3/4 | 124 | 49 | 44 | 13.5 | 1 to 10 | 25 |
| MKCM35-6TL-ON | Rc3/4 | 124 | 49 | 44 | 13.5 | 1 to 10 | 25 |
| MKCM45-6TL-OFF | Rc3/4 | 142 | 62 | 50 | 18.0 | 3 to 15 | 50 |
| MKCM45-6TL-ON | Rc3/4 | 142 | 62 | 50 | 18.0 | 3 to 15 | 50 |
| MKCM45-8TL-OFF | Rc1 | 142 | 62 | 50 | 18.0 | 3 to 15 | 50 |
| MKCM45-8TL-ON | Rc1 | 142 | 62 | 50 | 18.0 | 3 to 15 | 50 |
All dimensions are in millimetres. Select the complete model and connection rather than the nominal body size alone. Casting-based housings can have individual dimensional variations; check the product drawing and mounting clearance before installation.
Electrical installation and application limits
Observe the 300 V AC/DC, 0.5 A AC/DC and 50 VA contact limits together; the voltage and current maxima are not a permission to exceed the contact-capacity limit. Protect the reed switch from overcurrent and wiring faults. Nearby magnets or ferromagnetic parts can affect operation, so assess the installed location before commissioning. The manufacturer recommends using the switch as an alarm detector wherever practicable and considering the consequence of a malfunction when connecting it to other equipment.
Oil conditions, materials and special versions
Provide the actual oil grade or viscosity, operating temperature and required switch threshold when ordering. Changes in oil viscosity or temperature can move the switching point away from its original setting. Confirm the threshold under the intended operating conditions rather than assuming it is independent of the fluid. The standard acrylic tube allows the float to be observed. Heat-resistant and pressure-resistant options replace it with a C3604 brass tube and use fluororubber seals, so those versions lose the standard transparent-tube viewing function. Confirm the chosen special-version rating and materials when ordering.
Product and dimensional illustrations
Information to provide when ordering
Specify the complete OFF or ON model, oil type or viscosity, operating temperature, normal line flow, required switching flow and lead-wire arrangement. Confirm whether the standard transparent construction or a heat/pressure-resistant brass-tube version is required.