# IEC pushbutton contact: mushroom head normally open latching Canonical URL: https://eloragrid.ai/symbols/iec-pushbutton-contact-mushroom-head-normally-open-latching Publisher: Elora Grid Updated: 2026-10-28 Lookup label: PB Drawing use: Schematic Reference families: IEC, Manufacturer ## Symbol convention Convention: IEC Form: Mushroom Head Normally Open Latching Autodesk IEC-60617 Symbol Preview: Push Buttons, HPB11ML / VPB11ML. This identifies the publisher's library context; exact IEC graphics and database identities are not asserted. Pushbutton contact form: Mushroom Head Normally Open Latching. ## In plain English ### What does IEC pushbutton contact: mushroom head normally open latching mean? A pushbutton translates a person pressing an operator into a change of electrical contact state. The operator form and the contact state are separate pieces of information, so a mushroom head can operate either a normally-open or a normally-closed contact. This entry identifies the mushroom head normally open latching form in the publisher's IEC-context family. ### A simple example On a machine control sheet, this form lets the reader distinguish the physical button action from the contact used by the controller. Link every contact block to the same operator tag, including a separate indication lamp when fitted. The normally-open designation starts with a non-conducting output or open contact in the documented reference condition; operation changes that state. The mechanism keeps its operated position until its specified release action; releasing hand pressure alone is insufficient. ### What the drawings help you do The head shape and contact drawing do not establish a safety category, contact rating or emergency-stop suitability. Direct opening, reset behaviour and the selected assembly must be confirmed from its documentation. ### This particular reference Pushbutton contact form: Mushroom Head Normally Open Latching. This entry adds the mushroom head normally open latching detail to the broader pushbutton contact family. The head shape and contact drawing do not establish a safety category, contact rating or emergency-stop suitability. Direct opening, reset behaviour and the selected assembly must be confirmed from its documentation. ### Terms - Normally open / normally closed: The contact state in the normal condition defined for the drawing. - Signal: Electrical information passed between devices, rather than necessarily the main power supply. - Rating: A value stating the conditions for which equipment is specified. Concept diagram: Identify the device and form → Read the connections and state → Check the equipment reference A guide to reading this reference. The original symbol illustration and its drawing notes appear below; these boxes are not a wiring diagram. - [Pushbutton contact and actuator variants](https://help.autodesk.com/cloudhelp/2021/ENU/AutoCAD-Electrical/files/GUID-9E8890C7-7176-47DD-8700-E02A16C1670E.htm) ## What it represents A pushbutton translates a person pressing an operator into a change of electrical contact state. The operator form and the contact state are separate pieces of information, so a mushroom head can operate either a normally-open or a normally-closed contact. This entry identifies the mushroom head normally open latching form in the publisher's IEC-context family. On a machine control sheet, this form lets the reader distinguish the physical button action from the contact used by the controller. Link every contact block to the same operator tag, including a separate indication lamp when fitted. The normally-open designation starts with a non-conducting output or open contact in the documented reference condition; operation changes that state. The mechanism keeps its operated position until its specified release action; releasing hand pressure alone is insufficient. The head shape and contact drawing do not establish a safety category, contact rating or emergency-stop suitability. Direct opening, reset behaviour and the selected assembly must be confirmed from its documentation. ## How to read it - The normally-open designation starts with a non-conducting output or open contact in the documented reference condition; operation changes that state. - The mechanism keeps its operated position until its specified release action; releasing hand pressure alone is insufficient. - The head shape and contact drawing do not establish a safety category, contact rating or emergency-stop suitability. Direct opening, reset behaviour and the selected assembly must be confirmed from its documentation. ## Information to show or reference - Identify the operator and each associated contact block. - State the contact state before the operator is pressed. - Show the release or return action and any independent lamp supply. ## Important distinction This entry adds the mushroom head normally open latching detail to the broader pushbutton contact family. The head shape and contact drawing do not establish a safety category, contact rating or emergency-stop suitability. Direct opening, reset behaviour and the selected assembly must be confirmed from its documentation. ## Facts - Drawing form: Mushroom Head Normally Open Latching - Public vendor block names: HPB11ML / VPB11ML. Autodesk identifiers, not standards database IDs. - Drawing purpose: pushbutton contact - Graphic scope: Independently authored educational illustration; not certified standard geometry, a terminal pinout or a product footprint. ## Public references - [Pushbutton contact and actuator variants](https://help.autodesk.com/cloudhelp/2021/ENU/AutoCAD-Electrical/files/GUID-9E8890C7-7176-47DD-8700-E02A16C1670E.htm) — Autodesk. Public Push Buttons table explicitly lists HPB11ML / VPB11ML with this operating or connection form. Vendor graphics are linked, not copied. ## Graphic scope Independent original educational concept illustration by Elora Grid. Not a certified standards graphic or manufacturer footprint. Unitless; not to scale. Original artwork licence: https://creativecommons.org/licenses/by/4.0/. Publisher material is linked only.