Dear All.

From EN60529:1991, IP5x provides protection from dust ingress and penetration by an "access probe" of 1mm diameter. I imagine in this context a hazard would arise if the probe was conductive as this could cause the equipment to go wrong, potentially causing a hazard. The access probe is a rigid wire of 100mm long. An optional "Additional Letter" denotes protection from access to hazardous parts, ( which I include parts that if damaged of shorted out caused a hazard). Additional letter D denotes
protection from access to hazardous parts by the test probe by means of physical barriers or separation distance

As you say IPx4 provides protection from "splashing" from all directions. We made the spray head as defined in the standard, and I would be surprised if there were many commercial systems out there that would actually prevent ingress. The question is, would there be sufficient ingress to cause faulty operation at the time of the ingress, but more importantly, will the ingress promote corrosion of internal components causing unreliable operation of the unit at some time in the future?

If your equipment has drain holes such that fluid cannot accumulate, ( and your internals are protected) then fluid ingress is not so much of a problem. If you cannot damage your equipment by insertion of the probe in your sounder hole then that is not so much of a problem either.

As regards 3.5mm jack sockets, I dislike them, but they are compact. Wherever possible we put Stereo PCB jack sockets inside another small enclosure and feed the individual switch wires through a slotted foam cable "gland". This also prevents the plug being pulled out. Fully waterproof switches are available from QED.

If you "soak" a 3.5mm jack socket with a plug in it, does the water penetrate far enough to

        a) cause long term corrosion?

        b) cause unwanted activation of the input or output. This will depend on the impedance level that the circuit begins to operate at, and the conductivity of the fluid.

It is probably unreasonable to test equipment with sockets without plugs in, if that is the way they will be used in service. Unused sockets should therefore be fitted with covers.

You can get water proof "D"type and DIN connectors to IP67 from RS components etc, they are expensive but I consider it worth it.

My best advice is to buy a copy of the standard, chose your components carefully, and if necessary test to the applicable level of protection and see what happens.

Best regards,

        Geoff

G.J. Harbach  I.Eng  MIED  IIPEM
Clinical Technologist
Special Controls Service Manager
Posture and Mobility Services
West Midlands Rehabilitation Centre
91 Oak Tree Lane, Selly Oak
South Birmingham Primary Care NHS Trust
West Midlands.
Tel  0121  627 1627 Ext. 53238






        -----Original Message-----
        From:   p=NHS NATIONAL INT;a=NHS;c=GB;dda:RFC-822=ASSISTECH(a)JISCMAIL.AC.UK;
        Sent:   Wednesday, April 24, 2002 1:55 PM
        To:     p=NHS NATIONAL INT;a=NHS;c=GB;dda:RFC-822=ASSISTECH(a)JISCMAIL.AC.UK;
        Subject:        Ingress Protection

        Folks, I have a concern about IP ratings. When trying to decide what IP
        rating my wiseDX (www.wisedx.com) should meet my thoughts were:
        IP54 is the 'rain proof' liquid test informally thought of as the
        'outdoor' rating for equipment - where it is defined as being able to stand
        up to 'splashing' from ALL directions. It states that 'some ingress is
        permitted' (so long as it doesnt interfere with the workings I presume)
        The wiseDX display box could meet IP54 on account that all the components
        are rated at IP54 - except that I have a 2mm hole in the side for  noise to
        come out. I consider this hole stops it from being rated at IP54. I have not
        formally tested it. I consider that the main box of the wiseDX would not
        meet IP54 on account of its sockets - in particular the mini DIN and 3.5mm
        jack sockets.
        The manual for a REMG80 joystick says it meets IP54(pending). How can this
        be if it has a DIN connection and (on some models) 3.5mm sockets. Somebody
        (in a reply to scanning controllers on this listserve) has suggested or
        assumed that the 'Click To Go' would be IP54 rated. I cannot see how as it
        has lots of sockets for liquid to get through.
        I am interested to know what rating others consider as 'Outdoor proof' and
        do people think that if equipment has a 3.5mm jack socket or a mini DIN
        connector it would not meet an IP54 rating?

        Colin Clayton