REES CABLE SWITCHES – WHAT YOU NEED TO KNOW
By: Jena Stuckey and Luke Frey
Rees has been manufacturing control switches since 1929. While push buttons were initially our main focus, cable switches came into play shortly after and have made a splash in numerous industries. It is my hope that by providing a clearer understanding of the cable/rope switches Rees provides that we will be able to better assist you by helping you pinpoint which products will fit your needs.
Rees has one style of a broken cable detection switch. With this, the cable is stretched tightly until the shaft end is flush with the indicator hub end. The switch will trip and latch if the cable breaks, comes loose or is pulled. The blue booted reset button is pushed to reset contacts back to their normal operating configuration. These switches have been designed to reduce “nuisance tripping” from cable expansion and stretch often associated with taut cable switches. It also has the option of a pilot light or a blue button guard to protect the reset button in high traffic areas. The maximum recommended cable length is 200 feet with a maximum interval support of 10 feet. These switches are typically found on process applications such as conveyors, transfer machines or assembly lines within the automotive, machine tool, foundry and pharmaceutical industries.
Our standard cable operated switches have a slack cable style with positive break features. This makes the manual reset styles particularly competent for use in Emergency Stop applications as well as for ordinary circuit control. They are offered in both manual and automatic reset configuration. On the manual reset switches, the cable is connected on one end, and the t-handle on the other side is pulled to reset the switch. On the automatic version, the contacts return to original state once the cable is released. Rees also offers a food grade option that is coated a special white paint in order to withstand chemical wash-down. The maximum recommended cable length is 200 feet with a maximum interval support of 10 feet. These switches can be found on automated transfer machines and on various conveyor installations, with a heavy presence in material handling.
In the case that an indicator flag is preferred to see which switch has been tripped, we offer options for this! These are slack cable style switches that can be used in emergency stop applications, and are offered with single or double flag indicators. The independently operating red indicating flag rotates 90 degrees when tripped. Manually returning the flag to its normal position resets the switch. The maximum recommended cable length is 200 feet with a maximum interval support of 10 feet. These devices can be found on various conveyor installations.
Our bi-directional cable switch is a slack cable style that is activated by pulling the cable on either side. To reset the switch, the blue button on the cover is pushed. The maximum cable recommended cable length is 200 feet on each end with a maximum interval support of 10 feet. This switch can be found anywhere there is a conveyor and is often used in material handling situations. Just as with the broken cable switch, we offer a button guard to give extra protection in high traffic areas.
Our rope operated sequence switches are slack cable style with slow-make contacts. The switches are not positive transfer and they do not latch in any position. They should NOT be used for any emergency stop applications. The action of these devices is that when the switch actuating arm is pulled by a cable the switch contacts will change state, that is, the NO will be closed and the NC will go open. When the force on the cable is removed from the actuator arm, spring pressure will return it to its normal position, while the contacts are held in position through a ratchet mechanism. The next time the cable is pulled, the action is repeated with the contacts returned to their original state. The total maximum cable length recommended is 200 feet with a maximum interval support of 10 feet. These devices can be found on various conveyor installations as well as other stations that require the pull-on, pull-off function that this being provides.
If you’re looking for a cable switch that can be used vertically as well as horizontally, we offer options for this as well! These switches are a slack cable style with slow-make – slow-break contacts, making these NOT suitable for emergency stop applications. The function of these switches is such that a device that is listed as NO uses a NC contact Block which is held open by a spring in the switch body. Pulling of the ring eye collapses that spring, allowing the contact block to close and actuate the circuit it is connected to. Releasing of the rope then allows the spring to expand thereby opening the contacts. The momentary version can most often be found being used with a rope hanging down for control of an overhead door. The maintained style requires that resetting take place at the switch so access must be considered when installing it. The maximum recommended rope length is 33 feet with a maximum interval support of 10 feet when horizontal.
