Abstract:
An electrical test lead probe for use with a multi-meter provides for releasable retention in and electrical contact with a terminal of an industrial terminal block. The test lead probe includes a shortened body having an electrically conducting tip that is configured for releasable receipt into a terminal block socket of an industrial terminal block, the terminal block socket housing a terminal of the terminal block. The present terminal block probe, in one form, is permanently attached to a multi-meter test lead. In another form, the present terminal block probe is coupled to a modular multi-meter test lead. In yet another form, the present terminal block probe has a removable head incorporating an electrically conducting tip wherein the body is permanently attached to a multi-meter test lead. In a modular form, a plurality of terminal block probes may be provided each one of which has an electrically conducting tip of a different configuration corresponding to different configurations and/or sizes of industrial terminal block sockets.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention relates to equipment for taking electrical measurements of electrical circuits, components and/or devices and, more particularly, to multi-meter test lead probes for voltage measurement of control panel industrial terminal blocks. 
         [0003]    2. Background Information 
         [0004]    Industrial control systems use control panels to host electrical components that allow manufacturing processes to be automated. A common component among control panels is the industrial terminal block. Industrial terminal blocks have several uses within a control panel, but are used primarily to provide termination points between field devices and components within the industrial control panel. During system startup or troubleshooting, automation engineers and technicians use multi-meters such as digital multi-meters (DMMs) to take voltage readings at these industrial terminal blocks to help solve issues with the automated system. 
         [0005]    Electrical test leads with measurement tools such as probes are used in conjunction with DMMs in order to manually connect the industrial terminal blocks of the industrial control panel with the DMM in order to obtain the electrical measurement. There are two types of industrial DMM test leads: modular and non-modular. Non-modular test leads have a connector on one end to insert into a DMM while the other end has a probe. Modular test leads have connectors at both ends that can be inserted into a DMM and/or a probe. Modular test leads allow an engineer or technician to carry one set of test leads and multiple probes each one of which having a specific function. 
         [0006]    When taking electrical measurements of industrial control panel terminal blocks with present test leads (both modular and non-modular), the engineer or technician must use two hands: one to hold the neutral probe (typically black in color) and one to hold the positive voltage probe (typically red in color). Because of this, there are no free hands to hold and/or operate the DMM or to write or take notes. This can create an awkward situation. It would be advantageous if the user could have at least one free hand when taking a voltage measurement from an industrial terminal block of an industrial control panel. 
         [0007]    It is therefore evident from the above that there is a need for a tool that will enable a user to use only one hand when taking electrical measurements of an industrial terminal block via a multi-meter and multi-meter test leads. 
       SUMMARY OF THE INVENTION 
       [0008]    The present invention is a test lead probe for use with a multi-meter for releasable retention in and electrical contact with a terminal of an industrial terminal block. The test lead probe includes a shortened body having an electrically conducting tip that is configured for releasable receipt into a terminal block socket of an industrial terminal block, the terminal block socket housing a terminal of the terminal block. 
         [0009]    In one form, the present terminal block probe is permanently attached to a multi-meter test lead. In another form, the present terminal block probe is coupled to a modular multi-meter test lead. In yet another form, the present terminal block probe has a removable head incorporating an electrically conducting tip wherein the body is permanently attached to a multi-meter test lead. 
         [0010]    In the modular form of the present terminal block probe, a plurality of terminal block probes may be provided each one of which has an electrically conducting tip of a different configuration corresponding to different configurations and/or sizes of industrial terminal block sockets. In the case of multiple terminal block probes connectable to the modular multi-meter test lead, a terminal block probe kit is defined. Since there are multiple manufacturers of industrial terminal blocks, and each manufacturer uses different sizes of terminal blocks with different types and/or sizes of sockets, the use of a modular form of the present invention allows the user to easily take electrical measurements of various terminal blocks. Moreover, in the modular form, if two terminal block probes of the present invention are used on both ends of the multi-meter test lead, the test lead may be used as a jumper between terminal blocks. 
         [0011]    In the removable head form of the present terminal block probe, a plurality of heads are provided each one of which has an electrically conducting tip of a different configuration corresponding to different industrial terminal blocks. 
         [0012]    The present invention allows the user such as an engineer or technician to concentrate solely on the point of interest with the positive voltage probe. Moreover, if the engineer/technician would leave the control panel then return to take another voltage measurement, the neutral probe would be ready for use thus having only to grab the positive voltage probe. 
         [0013]    The shortened configuration of the body of the present control panel terminal block probe provides less strain on a terminal block than present multi-meter probes. 
         [0014]    The present invention will be more apparent upon reading the following detailed description in conjunction with the accompanying drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0015]    The above mentioned and other features and objects of this invention, and the manner of attaining them, will become more apparent and the invention itself will be better understood by reference to the following description of embodiments of the invention taken in conjunction with the accompanying drawings, wherein: 
           [0016]      FIG. 1  is a front view of an arrangement used to take voltage measurements from terminal blocks of a control panel utilizing a digital multi-meter and an industrial terminal block probe fashioned in accordance with the present principles; 
           [0017]      FIG. 2  is an enlarged side view of the industrial terminal block probe shown in  FIG. 1 ; 
           [0018]      FIG. 3  is a bottom view of the industrial terminal block probe of  FIG. 2  taken along line  2 - 2  thereof; 
           [0019]      FIG. 4  is a side view of multiple modular industrial terminal block probes for various types of industrial terminal blocks, each modular industrial terminal block probe utilizing a modular test lead, the multiple industrial terminal block probes constituting a kit and; 
           [0020]      FIG. 5  is a side view of an alternative embodiment of an industrial terminal block probe fashioned in accordance with the present principles and shown ready for reception in a contact of an industrial terminal block. 
       
    
    
       [0021]    Like reference numerals indicate the same or similar parts throughout the several figures. 
       DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0022]    Referring to  FIG. 1 , there is shown a digital multi-meter (DMM) generally designated  60  used to take voltage measurements of industrial terminal blocks  55  of an industrial control panel  50 . A first electrical test lead  11  is shown plugged into a positive voltage receptacle of the DMM  60  and may be considered a positive test lead, while a second test lead  13  is shown plugged into a negative, neutral or ground voltage receptacle of the DMM  60  and may be considered a negative, neutral or ground test lead (hereinafter collectively, neutral test lead). A conventional test lead probe  10  is attached to the positive test lead  11  and is adapted to be held by a user (e.g. an engineer or technician) and held in contact with a positive terminal or contact of one of the industrial terminal blocks  55  during a voltage measurement thereof. A terminal block probe and especially but not necessarily an industrial terminal block probe  12  (collectively hereinafter, an industrial terminal block probe) fashioned in accordance with the present principles is attached to the neutral test lead  13 . The industrial terminal block probe  12  is configured to be received by or inserted into a socket of a terminal block and especially but not necessarily an industrial terminal block  55  (collectively hereinafter an industrial terminal block  55 ) of the control panel  50 , be held within and/or by the socket of the industrial terminal block  55  and make contact with a terminal or contact of the socket of the industrial terminal block  55 . The terminal or contact of the terminal block socket is especially, but not necessarily, a neutral, ground or negative terminal or contact. In this manner and as shown in  FIG. 1 , the present industrial terminal block probe  12  is retained hands-free by the industrial terminal block  55 . 
         [0023]    Referring additionally to  FIGS. 2 and 3 , the industrial terminal block probe  12  is shown in greater detail. Particularly, the terminal block probe  12  consists of a body defined by a generally short cylindrical shaft  22  terminating at one end in a head  24  and including a circumferential finger grip  28 . The body  20  may be formed of plastic but other materials may be used. The head  24  is generally frusto-conically shaped that axially extends from the grip  28  and terminates in an electrically conducting tip  26 . The grip  28  is generally saucer shaped and includes a flat  29  on one side or edge thereof. The flat  29  provides a handling surface for the terminal block probe  12 . The shaft  22  includes an opening or socket  32  in which is situated an electrical pad or terminal  34 . The socket  32  and electrical terminal  34  are configured to receive a modular end of the test lead  13 . In this regard, the terminal block probe  12  is a modular type probe. While not shown, the probe  12  may not be modular and therefore be permanently connected to the test lead  13 . The terminal  34  is electrically connected to the electrically conducting tip  26  via a wire or the like  25  that extends through the body  20  from the terminal  34  to the tip  26 . 
         [0024]    The body  20  is sized to be relatively short compared to a typical test lead probe as is illustrated in  FIG. 1 . The axial length of the shaft  22  is short relative to the head  24 . In this manner, the probe  12  easily remains in the socket of the terminal block  55  without creating undue stress on the terminal block due to remaining therein without the additional support of a hand. 
         [0025]    Because each tip of a terminal block probe must be configured to be received the terminal socket of the terminal block, in accordance with an aspect of the present invention, reference is made to  FIG. 4  wherein there is depicted a plurality of terminal block probes  70  constituting a terminal block probe kit. As indicated above this is because each style (configuration) of terminal block (usually by manufacturer) typically has its own style (configuration) of a terminal block socket and thus terminal block socket terminal. In order to provide hands free voltage testing of a terminal block, it is necessary to have various terminal block probes having different tips corresponding to the configuration of terminal socket for a particular terminal block. 
         [0026]      FIG. 4  depicts three terminal block probes  12   a ,  12   b  and  12   c  representing any number of terminal block probes that may constitute a kit  70  of terminal block probes for use with a multi-meter for testing voltage at any one of a number of terminal blocks  55 . It should be appreciated that the representation of tips of the present terminal block probes are exemplary and not necessarily illustrative of any particular or true-to-life terminal block socket. The kit  70  may or may not include a modular multi-meter test lead  40 . The modular test lead  40  includes a probe plug  44  that is configured to be received by a socket  32   a ,  32   b  and  32   c  of respective probes  12   a ,  12   b  and  12   c . The probe plug  44  is electrically connected to a wire/lead  42  that terminates in a test lead plug  46 . The test lead plug  46  is adapted and/or configured to be received in an input of a multi-meter and/or a multi-meter test lead tool. 
         [0027]    The terminal block probe  12   a  is like probe  12  in composition, configuration and function. As such, the terminal block probe  12   a  and has a body  20   a  defined by a generally short cylindrical shaft  22   a  terminating at one end in a head  24   a  and including a circumferential finger grip  28   a . The body  20   a  may be formed of plastic but other materials may be used. The head  25   a  is generally frusto-conically shaped that axially extends from the grip  28   a  and terminates in an electrically conducting tip  26   a . The grip  28   a  is generally saucer shaped and includes a flat  29   a  on one side or edge thereof. The flat  29   a  provides a handling surface for the terminal block probe  12   a . The shaft  22   a  includes an opening or socket  32   a  in which is situated an electrical pad or terminal  34   a . The socket  32   a  and electrical terminal  34   a  are configured to receive the modular end  44  of the modular test lead  40 . In this regard, the terminal block probe  12   a  is a modular type probe. The terminal  34   a  is electrically connected to the electrically conducting tip  26   a  via a wire or the like  25   a  that extends through the body  20   a  from the terminal  34   a  to the tip  26   a.    
         [0028]    The body  20   a  is sized to be relatively short compared to a typical test lead probe such as is illustrated in  FIG. 1  with regard to probe  10 . The axial length of the shaft  22   a  is short relative to the head  24   a . In this manner, the probe  12   a  easily remains in the socket of the terminal block  55  without creating undue stress on the terminal block due to remaining therein without the additional support of a hand. 
         [0029]    The terminal block probe  12   b  is like probe  12  in composition, configuration and function. As such, the terminal block probe  12   b  and has a body  20   b  defined by a generally short cylindrical shaft  22   b  terminating at one end in a head  24   b  and including a circumferential finger grip  28   b . The body  20   b  may be formed of plastic but other materials may be used. The head  25   b  is generally frusto-conically shaped that axially extends from the grip  28   b  and terminates in an electrically conducting tip  26   b . The grip  28   b  is generally saucer shaped and includes a flat  29   b  on one side or edge thereof. The flat  29   b  provides a handling surface for the terminal block probe  12   b . The shaft  22   b  includes an opening or socket  32   b  in which is situated an electrical pad or terminal  34   b . The socket  32   b  and electrical terminal  34   b  are configured to receive the modular end  44  of the modular test lead  40 . In this regard, the terminal block probe  12   b  is a modular type probe. The terminal  34   b  is electrically connected to the electrically conducting tip  26   b  via a wire or the like  25   b  that extends through the body  20   b  from the terminal  34   b  to the tip  26   b.    
         [0030]    The body  20   b  is sized to be relatively short compared to a typical test lead probe such as is illustrated in  FIG. 1  with regard to probe  10 . The axial length of the shaft  22   b  is short relative to the head  24   a . In this manner, the probe  12   b  easily remains in the socket of the terminal block  55  without creating undue stress on the terminal block due to remaining therein without the additional support of a hand. 
         [0031]    The terminal block probe  12   c  is like probe  12  in composition, configuration and function. As such, the terminal block probe  12   c  and has a body  20   c  defined by a generally short cylindrical shaft  22   c  terminating at one end in a head  24   c  and including a circumferential finger grip  28   c . The body  20   c  may be formed of plastic but other materials may be used. The head  25   c  is generally frusto-conically shaped that axially extends from the grip  28   c  and terminates in an electrically conducting tip  26   c . The grip  28   c  is generally saucer shaped and includes a flat  29   c  on one side or edge thereof. The flat  29   c  provides a handling surface for the terminal block probe  12   c . The shaft  22   c  includes an opening or socket  32   c  in which is situated an electrical pad or terminal  34   c . The socket  32   c  and electrical terminal  34   c  are configured to receive the modular end  44  of the modular test lead  40 . In this regard, the terminal block probe  12   c  is a modular type probe. The terminal  34   c  is electrically connected to the electrically conducting tip  26   c  via a wire or the like  25   c  that extends through the body  20   c  from the terminal  34   c  to the tip  26   c.    
         [0032]    The body  20   c  is sized to be relatively short compared to a typical test lead probe such as is illustrated in  FIG. 1  with regard to probe  10 . The axial length of the shaft  22   c  is short relative to the head  24   c . In this manner, the probe  12   c  easily remains in the socket of the terminal block  55  without creating undue stress on the terminal block due to remaining therein without the additional support of a hand. 
         [0033]      FIG. 5  depict another embodiment of a terminal block probe, generally designated  76 , that provides modularity by utilizing removable heads that have variously configured tips. The terminal block probe  76  may thus be considered part of the test lead  70 . The test lead  70  includes test lead wire  72  terminating at one end in the terminal block probe  76  and at the other end in a multi-meter plug  74 . 
         [0034]    The terminal block probe  76  is similar in composition, configuration and function to the terminal block probe  12 . As such, the terminal block probe  76  has a body  77  defined by a generally short cylindrical shaft  78  terminating at one end in a truncated head  80  and including a circumferential finger grip  79 . The grip  79  is generally saucer shaped and may include a flat (not shown) on one side or edge thereof. The body  77  may be formed of plastic but other materials may be used. A tip assembly  83  having an electrically conducting tip  84  is removably received onto the head  80 . The test lead  72  is electrically connected to the electrically conducting tip  84  via a wire or the like (not shown) that extends through the body  77  from the test lead  72  to the tip  83 . The tip assembly  80  is one of various tip assemblies each one of which has a differently configured tip  84  to correspond with different configurations of terminal blocks. In this manner, only the head assembly of the probe  76  needs to be changed in order to accommodate different styles and/or configurations of terminal blocks, thereby creating another modular terminal block probe. 
         [0035]    The terminal block probe  76  of  FIG. 5  is shown ready to be inserted into a terminal block socket  56  wherein the tip  84  may contact the electrical terminal or contact  58  of the industrial terminal block  55 . The socket  56  and thus the terminal  58  are the neutral, ground or negative terminal or contact. The industrial terminal block  55  may as shown, but may not, include a second terminal block socket  57  having an electrical terminal or contact  59  which are also a neutral, ground or negative terminal or contact. Alternatively, the socket  56  and thus the terminal or contact  58  may be a positive terminal or contact rather than a neutral, ground or negative terminal or contact. In this case, should the industrial terminal block  55  include a second socket  57  and electrical terminal or contact  59  such as shown, the second socket  57  and terminal or contact  59  would also be a positive terminal or contact. 
         [0036]    The body  77  is sized to be relatively short compared to a typical test lead probe such as is illustrated in  FIG. 1  with regard to probe  10 . The axial length of the shaft  78  is short relative to the head  80 . In this manner, the probe  76  easily remains in the socket of the terminal block  55  without creating undue stress on the terminal block due to remaining therein without the additional support of a hand. 
         [0037]    While the invention has been illustrated and described in detail in the drawings and foregoing description, the same is to be considered as illustrative and not restrictive in character, it being understood that only preferred embodiments have been shown and described and that all changes and modifications that come within the spirit of the invention are desired to be protected.