I'm sure you already know your request was not a simple one. But your
wiring diagram is completed. It has been saved in two formats, so you
can use one or both as you choose. Simply click on the links or
copy/paste into your browser. When the page loads, look for a link
about two-thirds of the way down the box that says, "Click here to
download ...." You will have the choice of either opening the file(s)
directly or saving them to your computer, and then opening them from
your own location.
Here is a link to a .gif image of the diagram:
*Note: this image may require scrolling to view at normal size, so you
can either zoom out to see it as a whole, or print it out. It should
print on a standard 8 1/2 x 11" paper.
And here is a .pdf version of the same diagram:
*Note: you'll need Adobe Acrobat Reader to open/view the pdf file, so
if you don't already have that, you can download a free copy here:
General purpose relays were selected for this application rather than
motor starter contactors due to the small size of the motor, i.e. ¼
HP. According to Bison Tech support (1-800-282-4766), the inrush
current for model 756 motor is 3.5 amps (at 230 VAC). They agreed that
interposing relays rated at or above 10 amps would be well suited for
the power and reversing circuits for the motor.
Allen-Bradley relays were chosen due to the worldwide availability of
their products. The contacts on the selected relays are rated at 15
amps and are designed for inductive loads.
Therefore, your component list is as follows:
K1: Allen-Bradley General Purpose Relay 700-HB32A2 with relay base 700-HN154
K2: Allen-Bradley General Purpose Relay 700-HB32A2 with relay base 700-HN154
*Note: The relays listed above have a coil voltage of 230 VAC. This
voltage was selected to match the voltage that will be switched by the
specified PLC module, i.e. Siemens LOGO! 230RCo 6ED1 052 - 2FB00 -
In your clarification, however, you identified the control voltage
between the PLC and the relay as 24 VDC. If the relays' coils need to
operate on 24 VDC, then the part number for the relays K1/K2 will be
700-HB32Z24 instead of the one given above. Either way, the relay base
will be the same, i.e. 700-HN154, and the wiring diagram will not
Relay specifications can be found at:
Relay connection diagram can be found at:
Allen-Bradley-s online store is at:
http://www.rockwellautomation.com/rsstore However, the link does not
appear to be working.
To find a local distributor, follow this link instead:
I hope this provides you with everything you need to connect your
motor in the manner you need to. If not, or if anything is not clear,
or any links don't work, please ask for further clarification before
rating/closing your question, so I can be sure you have what you need.
I consulted with a professional electrical engineer of my acquaintance
who recommended and appropriately verified the suggested parts,
constructed the diagram, and let me know where to find the additional
Clarification of Answer by
23 Nov 2005 09:05 PST
You're very welcome! I'm so happy you were pleased.
To address your additional requests:
1) The Siemens 3TX7114 series of relays will work for your
application. You will need to purchase the following items:
3TX7114-5LG13 RELAY 240 V AC DPDT 15 A
3TX7144-1E6 Socket for 3TX7114
3TX7144-1L1 Hold/eject clip for 3TX7114
Depending on whether you mount the relays on DIN rails or on a panel,
you will also need one of the following:
3TX7144-3L5 Flange adapter for 3TX7114
3TX7144-3L4 DIN adapter for 3TX7114
Relay Specifications may be found at:
Relay Wiring Details are loacted at:
To locate a Siemens distributor in your area, first go to the main
Siemens website, here:
http://siemens.com/index.jsp to choose your country/language. Or if
you'd like to check out online retailers, use this link instead:
The wiring diagram has been revised to match the connection
configuration of the Siemens 3TX7114 relays. Note the change in pin
numbers. If 24 VDC coil is used rather than the 230 VAC coils, replace
the relay specified above with 3TX7114-5LC03. The (+) and (-)
designations shown near the relay coils on the connection diagram are
provided for use when using the 24 VDC relays.
The revised wiring diagram is here:
2) I would be happy to work with you again. If you have additional
questions in future, and would like to direct any of them to my
attention, simply put "For Byrd-ga only" or something similar in the
subject line of your question, then proceed normally. My colleagues
will see and respect such a request. Thank you for asking.
Of course, as before, if anything isn't clear, please be sure to ask
for a clarification before rating and closing the question.