Emergency Shutdown Switch per IEC 60947-5-1
Emergency Shutdown Switch per IEC 60947-5-1
(OP)
I am looking for a push-button operated emergency shutdown switch for use at up to 400 amps, 12V DC and up to 200 amps, 24V DC for winches per an EN standard. These are full-load amps for the winches. At stall torque the motor may draw 50% higher current which I assume should be the max. switch rating (600 amps 12v, 300 amps 24v).
The IEC spec is called out in the EN winch standard and also says "switch shall be of the self-latching type and shall have positive (direct) opening action. Actuator shall be of the palm or mushroom head type, colored red, with the background around the actuator colored yellow"
Are the above requirements specified in the IEC spec and does anyone know any manufacturerers of such a switch? I do not have a copy of the spec.
Thanks,
The IEC spec is called out in the EN winch standard and also says "switch shall be of the self-latching type and shall have positive (direct) opening action. Actuator shall be of the palm or mushroom head type, colored red, with the background around the actuator colored yellow"
Are the above requirements specified in the IEC spec and does anyone know any manufacturerers of such a switch? I do not have a copy of the spec.
Thanks,





RE: Emergency Shutdown Switch per IEC 60947-5-1
There are loads of manufacturers for the emergency stop switches themselves. In roughly alphabetical order: ABB, Allen Bradley, Bartec, Craig & Derricott, Moeller, Siemens, Telemecanique... too many to keep going! The contactor would probably be from someone like Hubbell or the like specialising in heavy current low voltage DC applications. The winch presumably has a contactor, so maybe you can interface to this?
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If we learn from our mistakes I'm getting a great education!
RE: Emergency Shutdown Switch per IEC 60947-5-1
RE: Emergency Shutdown Switch per IEC 60947-5-1
We currently have two types of emergency shutdowns. One is as you describe: it is a NC solenoid (separate from the winch operating solenoids) in the + cable and a toggle switch is used to open the solenoid to shutdown power to the main solenoid. The problem is with this requirement:
"switch shall be of the self-latching type and shall have positive (direct) opening action." It has neither of these features.
The other shutdown switch we offer is a manual switch which directly opens and closes the contacts which are rated for even higher current than needed, but this switch does not meet the requirement. It has positive opening action, but cannot be operated by a remote push button switch.
Is there another interpretation of the requirement?
RE: Emergency Shutdown Switch per IEC 60947-5-1
This link shows a typical example. http
Electrically the switch is closed when the switch is not pressed, and open when the switch is pressed. The switch mechanically latches when pressed.
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If we learn from our mistakes I'm getting a great education!
RE: Emergency Shutdown Switch per IEC 60947-5-1
What you say makes sense. Looks like we would want to use the stay-put, either pull to release or the button release. If I understand the spring return, it is momentary, so the stop solenoid would not stay open. Would the pull to release be the best choice?
This looks like the solution that would be used in conjunction with the push button hold-to-run remote control switch.
RE: Emergency Shutdown Switch per IEC 60947-5-1
I tend to use the stay-put, twist-to-reset style of push button E-stop, but there are many variants for different applications and operational conditions. I've used the key reset type in a different industry to the one I work in now so that a line can't be restarted from a E-stop condition except by a supervisor or engineer.
I'm not 100% certain I understand how your winch switches on and off. Most contactors have one coil which energises and closes the contacts, and opens the contacts when the coil is de-energised. They're pretty simple to add an E-stop function. Does this scheme have separate solenoids to energise and de-energise the motor? That will be a little more complicated. Have you got an internal wiring diagram for this winch?
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If we learn from our mistakes I'm getting a great education!
RE: Emergency Shutdown Switch per IEC 60947-5-1
Looks like the location of the E-stop switch should be between the rocker switch and the shutdown solenoid. The E-stop would be NC. The emergency shutdown solenoid is NO (my original post said NC which is incorrect).
Do you agree?
RE: Emergency Shutdown Switch per IEC 60947-5-1
Purely for my own curiousity, how do these solenoids control the winch? Are they mechanically locking the drum?
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If we learn from our mistakes I'm getting a great education!
RE: Emergency Shutdown Switch per IEC 60947-5-1
If the E-stop is between the rocker switch and the shutdown solenoid, then if it de-energises, the winch will stop because the shutdown solenoid will open.
Thanks for your help.