My First Standard Electric Master Clock - Now What?

Discussion in 'Electric Horology' started by David J, Mar 17, 2013.

  1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.
  1. David J

    David J Registered User

    Jul 27, 2001
    75
    0
    6
    Richmond, VA
    Country Flag:
    Region Flag:
    #1 David J, Mar 17, 2013
    Last edited: Mar 17, 2013
    I just acquired my first SET master clock, and I am hoping the experts here can get help me figure out how to get it started. I would like to get the clock running and drive three slaves clocks - one 18" slave and two 12" slaves that are contained in a two sided corridor bracket. I have included pictures of the master and slaves, and I do have the original wood rod pendulum. I can clean the movement, but once I have that done, what do I do next? What is the function of all those switches, coils, etc. found in the case? I have many questions, and thank you for any help you can provide to get me started.

    David
    www.antiquetimeclocks.com
     

    Attached Files:

  2. eskmill

    eskmill Registered User
    NAWCC Fellow NAWCC Member

    Aug 24, 2000
    7,135
    31
    0
    Region Flag:
    David J's photos reveal a nice albeit a little dusty example of a school master clock with some equally handsome slave clocks. It is one of the older and simpler models. It is a "minute impulse type and has no automatic correcting capability that later and more complex models, the AR versions have.

    The bell duration timer shown at the right of the movement times the length of the school hallway bells I believe. I don't recall ever seeing one and I believe that later master clocks used a set of contacts on the movement for the same function as far as I know.

    The large black old style capacitor was likely added to suppress contact arcing. The carbon shunt resistors mounted above each relay suppress arcing as well. Arcing contacts erode the metal of the contacts shortening the working life of the the contact. Some of the contacts used precious metal....don't use sandpaper to clean contacts made with platinum.

    Of the two thumb keys in the lower part of the case, one is used to advance connected slave clocks one minute for each depression. The other key force-winds the master movement. Initially, when the clock is run-down, this key is pressed 54 times to wind the helical mainspring fully. The lever switches are used to control connected slave clocks and controlled bells and buzzers.

    The two tightly coiled wires attached from the top inside of the case down to the verge are unusual. Generally there's only a single connecting wire to control the movement winding electromagnets. Obviously there is a second set of oscillating contacts making very brief connection between the verge oscillating leaf spring and a rotating contact arm on the escape wheel arbor.
     
  3. David J

    David J Registered User

    Jul 27, 2001
    75
    0
    6
    Richmond, VA
    Country Flag:
    Region Flag:
    Les:

    Great information & thanks. It makes sense to me. Now, I assume that the mainspring is wound by a battery in a similar manner as a Self Winding Co. clock. If so, how do I power this clock to keep it running?

    David
     
  4. Ingulphus

    Ingulphus Registered User

    May 29, 2006
    723
    3
    18
    Oakland, CA
    Country Flag:
    Region Flag:
    Your SETCO master was re-wound by power most likely originally supplied by an AC rectifier or DC line current; the voltage is commonly (though not invariably) 24 VDC, whereas most SWCC clocks use 3 VDC. And SWCC clocks use a vibrating mechanism, such as you'd find on an older electric bell to wind a conventional mainspring one an hour, but SETCO clocks utilize a helical spring which is wound once a minute via an electromagnet when the winding contact on the EW arbor makes.

    I power mine using a power source/impulser from Ken's Clock Clinic, which uses 4 D cells and bypasses the oscillating contact to send an impulse to the winding coil once a minute. There may be some drawbacks to using it; please read Eckmill's comment here: https://mb.nawcc.org/showthread.php?75344-SET-AC-connect-question&highlight=setco+ken%27s+clinic. I must say that, while my SETCO has been running flawlessly since I installed Ken's impulser, I have not had the movement out to inspect the EW teeth to see if there has been excessive wear.

    The impulser can drive a master clock or a slave, but it cannot do both unless each uses the same voltage; you would need to set up a second power supply for the slaves (which again may require anything from 1.5 VDC on up). A second impulser would do the trick, but you may rather have the master clock itself drive the slaves, using the second contact on the EW (one of the two coiled wires coming down from the top of the case to the verge) and its mating leaf spring contact. You'll need to test the wiring paths to determine how to wire in the power source so you can use the advance key on the master to advance the slaves.
     
  5. David J

    David J Registered User

    Jul 27, 2001
    75
    0
    6
    Richmond, VA
    Country Flag:
    Region Flag:
    Ingulphus,

    Thanks for your reply. I would rather have the master clock drive the salves which I understand is not possible with the impulser you mentioned from Ken's. If I want to do this, what would be my power options?

    David
     
  6. harold bain

    harold bain Registered User
    NAWCC Member Deceased

    Nov 4, 2002
    40,850
    162
    63
    Male
    deceased
    Whitby, Ontario, Canada
    Country Flag:
    Region Flag:
    First, find out what voltage you need for both winding the clock, and running the slaves. Then make a power supply (transformer and rectifier) of suitable voltage. You may need to make up a variable voltage power supply to test to see what you need. Are the slaves from the same installation as the master clock? I have one Standard slave running off my 24 volt power supply from my Stromberg master clock (mixed in with IBM slaves in parallel). I had to install a series resistor on this slave to bring the voltage down to where it wasn't overloading the slave coils.
     
  7. eskmill

    eskmill Registered User
    NAWCC Fellow NAWCC Member

    Aug 24, 2000
    7,135
    31
    0
    Region Flag:
    There's sometimes no voltage notation on these older master clocks. It's usually 24 volts DC and needs less than one ampere. The proof is sometimes determined by connecting a variable DC power supply, carefully applying first 3 volts and gradually increasing the voltage up about 28 volts while watching for smoke. :mad: Often the black fiber ends of the electromagnet spools is stamped with the wire gauge, usually 29 or 32. Too sometimes the voltage is marked near the terminals atop the clock.

    Although 24 volts DC is usually what's needed, I personally have found that lap-top chargers are an excellent source of either 19.5 or 24 volts of accurately regulated DC. and internally protected for short circuit but an external 2 or 3 amp fuse protects is advised.

    Most SET master clocks designed for 24 volts are said to be tested to operate reliably at 18 volts at the time of manufacture. Second-hand lap-top chargers can usually be found for five dollars or less. Voltage polarity on YOUR SET master clock is unimportant as there are no polarity sensitive components that I see in your photos. Still it is nice to get it right with the common buss atop the clock as negative.
     
  8. wheelgun357

    wheelgun357 Registered User

    Nov 20, 2008
    163
    1
    16
    Involves a Badge
    Philly, PA
    Country Flag:
    Region Flag:
    FyI Kens now makes an impulses that drives both the master and up to two slaves and I think he can make one to drive 3 slaves and the master at once........ Look at his site he recently updated and I am using one right now.... Nicer new design too....
     
  9. David J

    David J Registered User

    Jul 27, 2001
    75
    0
    6
    Richmond, VA
    Country Flag:
    Region Flag:
    Harold:

    How does one make a variable power supply? The slaves are likely not from the same installation.

    David
     
  10. David J

    David J Registered User

    Jul 27, 2001
    75
    0
    6
    Richmond, VA
    Country Flag:
    Region Flag:
    Les:

    I have a couple of old laptop chargers that look to have an output of 20V DC. How would I devise a way to connect the charger to my master with a 2 or 3 amp fuse between the two? If it helps, it looks like the original wires that went from the master to the slaves and bells was 14 gauge.

    David
     
  11. David J

    David J Registered User

    Jul 27, 2001
    75
    0
    6
    Richmond, VA
    Country Flag:
    Region Flag:
    Wheelgun357 -

    Yes, I saw the new option to drive more than two slaves. I would like to run the master as it was originally intended, and it sounds like Ken's impulser sort of bypasses the ability to advance the slaves or wind the spring from the master. Am I correct? Thanks.

    David
     
  12. harold bain

    harold bain Registered User
    NAWCC Member Deceased

    Nov 4, 2002
    40,850
    162
    63
    Male
    deceased
    Whitby, Ontario, Canada
    Country Flag:
    Region Flag:
    David, I use a variac (an adjustable transformer) and a voltmeter to see where I'm at. If you had enough battery holders that fit C or D batteries, you could hook them up in series, adding one extra battery at a time until you find the voltage that picks the advance coils on the wall clocks, and/or winds the master clock.
     
  13. eskmill

    eskmill Registered User
    NAWCC Fellow NAWCC Member

    Aug 24, 2000
    7,135
    31
    0
    Region Flag:
    It would be helpful to post a photo of the terminals atop the clock. Move all the red wires aside, they appear to be wiring going to the slaves and to school hallway bells as well as a source DC of the proper voltage for the master movement and connected slaves. An additional power connection is usually necessary to provide voltage to operate the bells. Some installations used alternating current for the bells separate from the master/slave power source. Often there's some cryptic notations in pencil near the connecting blocks on the top of the clock. Thus there's usually two power sources and connection blocks for the two separate power sources.

    A fact to know before you try impulsing your nice wooden slave dials, is that some were intended to be connected in a series pf eight connection or daisy-chain manner as are some Christmas tree lamps. A series connection of eight provides 3 volts for each slave clock. There's no rule but generally, the clocks with longer hands require the full 24 volt impulse and are connected in a parallel manner. To use one of the 3 volt clocks in parallel connection requires a series resistor to reduce the voltage from 24 down to 3 volts. I recall using 120 ohm resistor for one of the low voltage slave dials.
     
  14. David J

    David J Registered User

    Jul 27, 2001
    75
    0
    6
    Richmond, VA
    Country Flag:
    Region Flag:
    Les:

    I attached a picture of the top of the case with what I believe to be the correct markings by each terminal. I do have a question on a couple. What does this information tell you about my clock? Thanks for the help.

    David
     

    Attached Files:

  15. wheelgun357

    wheelgun357 Registered User

    Nov 20, 2008
    163
    1
    16
    Involves a Badge
    Philly, PA
    Country Flag:
    Region Flag:
    they can be advanced and wind the master.... It's a great system and it bypasses using the contacts and wearing out the escape wheel..... I love the system,.. Also it eliminates the wall wart power
     
  16. harold bain

    harold bain Registered User
    NAWCC Member Deceased

    Nov 4, 2002
    40,850
    162
    63
    Male
    deceased
    Whitby, Ontario, Canada
    Country Flag:
    Region Flag:
    And it also has the option of the wall wart, if you don't want to feed it batteries. I used one a few weeks ago, and was quite impressed with it.
     
  17. eskmill

    eskmill Registered User
    NAWCC Fellow NAWCC Member

    Aug 24, 2000
    7,135
    31
    0
    Region Flag:
    I don't know how to tell you how to make a variable supply. That is beyond the purpose of this forum.
    First examine the slave mechanism and any labels to learn the required voltage connection. If no data available, first try connecting to 3 volts....two flashlight cells in series. If the electromagnet snaps quickly and the hands move. It is a 3 volt slave and needs a series resistor of about 150 ohms more or less to operate on 24 volts.
     
  18. eskmill

    eskmill Registered User
    NAWCC Fellow NAWCC Member

    Aug 24, 2000
    7,135
    31
    0
    Region Flag:
    Thanks for the photo of the top of the case. Unfortunately I'm away on vacation and don't have the software to clear and enhance the picture so it can be compared with layouts I have seen and worked with. I will look over the picture in a week or two.
     
  19. eskmill

    eskmill Registered User
    NAWCC Fellow NAWCC Member

    Aug 24, 2000
    7,135
    31
    0
    Region Flag:
    Wheelgun 357 replied in part:"It's a great system and it bypasses using the contacts and wearing the escape wheel..."
    I agree Ken's system is great and a very useful device for using certain types of slave and some simple master clocks. But it's use defeats the kind of precise impulse to the winding system of the master movement that is required to minimize the damage to the escape wheel on the Standard Electric Time Co. master movement in the thread under discussion.

    The older SET system, was very popular and reliable. When SET supplied repair parts, one of the most often replaced parts was said to be the escape wheel because the teeth were badly worn. SET made new escape wheels wider but that does not cure the problem. Only precise timing of the winding impulse and attention to winding pawl adjustment will cure the curse.

    Using a random winding impulse for the SET master movement does work and is satisfactory to demonstrate the SET master clock. However, a random winding impulse can cause accelerated wear on the escapement wheel. It is harmful. DO NO HARM.



     
  20. David J

    David J Registered User

    Jul 27, 2001
    75
    0
    6
    Richmond, VA
    Country Flag:
    Region Flag:
    ** UPDATE **

    With the advice gathered here, I was able to get my SET master clock up and running. I found an old laptop battery charger that outputs 20V and connected it to the #1 and T2B(?) contacts at the top of the clock as shown in the attached picture. Everything seems to run great after a few adjustments. The program control is giving me a few issues, but I need to adjust the program control point/arm a little to make sure the program consistently moves when the winding arm is in motion. All of the buttons and and switches work. So, I can wind the clock using the switch at the bottom of the case, and the slave relay activates when I push the switch for the sales at the bottom of the case.

    My next mystery - how to connect three slaves to the clock? I have three slaves with the same type of movement pictured below which I think is a correcting version. I know that my clock does not have the correcting feature, so can I still run slaves meant for a correcting master from my non-correcting master?

    If so, where do I connect the wires at the top of the clock and at the slaves? Thanks for the feedback.

    David
     

    Attached Files:

  21. Ingulphus

    Ingulphus Registered User

    May 29, 2006
    723
    3
    18
    Oakland, CA
    Country Flag:
    Region Flag:
    David -

    Advice from an amateur; the experts will have a better explanation.

    First, you'll need to determine the correct voltage for each slave movement; despite the name Standard Electric, I believe the company provided master and slave clocks to each customer's specs. I have a marble-dial slave from the 20s that requires 1.5 v to advance, but I have three from 1956 that require more (they're packed away, so I can't confirm the voltage). Test each slave with 1.5 volts (one D cell battery) and then try 3, 4.5, and so forth. Use the C (common) terminal and the M (I'm guessing the R terminal is for the correction coil). If all three use the same voltage, you can consider wiring them in series, with the minimum voltage multiplied by three to determine the load for all (if they were 3 v, a 9-volt battery should do it).

    To determine the connection points on the master, trace the wires from the slave contacts (not the winding) on the master movement to their terminals on the top of the case. There should also be a ground or common connection for the circuit. Check for arcing; you may have to add a resistor across the terminals to act as a shunt.

    - Mark
     
  22. David J

    David J Registered User

    Jul 27, 2001
    75
    0
    6
    Richmond, VA
    Country Flag:
    Region Flag:
    Mark:

    Thanks. That worked and I have the first slave working great. Now, what is the proper way to connect two in a series if they both have the same wiring block as shown in my previous picture?

    David
     
  23. Ingulphus

    Ingulphus Registered User

    May 29, 2006
    723
    3
    18
    Oakland, CA
    Country Flag:
    Region Flag:
    David-

    I may have this wrong, but try connecting the line out from the master to one of the terminals on the first slave. Connect the other slave terminal to one on the second slave. Connect the second terminal of the second slave to the common on the clock. You are creating a loop for the circuit, and it should make your line current drop by 50% (i.e. if you have a 9v source, you'll get approximately 4.5 at each slave). I don't believe polarity is an issue, so as long as the current is passing through the slave coils, they should advance simultaneously.

    Best regards,

    Mark
     
  24. David J

    David J Registered User

    Jul 27, 2001
    75
    0
    6
    Richmond, VA
    Country Flag:
    Region Flag:
    All seems to be functioning well. I installed a 3 amp fuse to protect the clock as suggested. I have determined that one of my slaves is not working quite right, so I need to investigate.

    Another problem relates to the program mechanism. On each impulse, the program mechanism does not advance completely. So, the tape ends up being slow over time. I have linked a short video on YouTube showing exactly what happens on each impulse. Does anyone have any suggestions as to how I can fix this problem? Thanks for the feedback.

    David
     
  25. Tinker Dwight

    Tinker Dwight Registered User

    Oct 11, 2010
    13,666
    70
    0
    Calif. USA
    A little less tension on the tapes or more spring on the lever.
    Tinker Dwight
     
  26. eskmill

    eskmill Registered User
    NAWCC Fellow NAWCC Member

    Aug 24, 2000
    7,135
    31
    0
    Region Flag:
    #26 eskmill, Mar 30, 2013
    Last edited: Mar 30, 2013
    Your video showing the attempt to advance the bell program tape and the accompanying audio suggests that the timing of the movement winding magnets occurs at the "top" of the minute while the bell programmer timing occurs at the half-minute or the "bottom" of the minute. This is generally the accepted sequence. It also reveals that the bell program motor or electromagnets are impulsed by a circuit timed by a pair of contacts actuated by a small cam on the escape wheel arbor.

    he duration of the bell tape program impulse should be strong and long enough to rotate the tape sprockets. The paper tapes are a minimal mechanical load.
    Usually the duration of the contact closure is fixed by the dimension of the platinum metal portion of the cam and that the contact closure occurs wen the escape wheel arbor is dead still.

    The loud 120 cycle hum I hear in the audio recording suggests a strong AC component from your 24 Volt source. A well filtered DC source has little or no ripple that would produce an audible humming sound from the bell tape program electromagnets. It is likely that the current energizing the bell tape programmer is weak. Here is a good opportunity to connect a DC volt meter or a test lamp to the bell programmer connections. Observe the DC voltage while manually closing the circuit to energize the bell programmer.

    It is also possible that the bell programmer mechanism requires maintenance adjustment. The same movement is also used in the largest clock dials.
     
  27. David J

    David J Registered User

    Jul 27, 2001
    75
    0
    6
    Richmond, VA
    Country Flag:
    Region Flag:
    Les, Thanks for the information. I have a couple of comments and more questions below.

    The slave circuit activates at the 60 second mark while the winding and program mechanism activate at the 30 second mark.

    The program mechanism runs fine without the tape on the sprockets. I have attempted to reduce any drag initiated by the sprockets with no luck. The mechanism does not advance all the way each on each impulse. Is there a spring that I should inspect behind the mechanism? My best guess is that I need a little more force to move the mechanism into the proper resting position on each impulse. I am a little apprehensive about taking the mechanism out of the case.

    I do not hear a loud hum, but your ears are trained to hear such a sound I guess. My power supply (old laptop AC/DC charger) was delivering 19.6 volts to the terminals on the master. I found another source that is now delivering 23.9 volts to the master, and the clock and slave function the same as before with 19.6 volts. I did have a slave that would not run at 19.6 but now seems to work with 24 volts. How do I manually close the circuit on the program mechanism?

    David
     
  28. David J

    David J Registered User

    Jul 27, 2001
    75
    0
    6
    Richmond, VA
    Country Flag:
    Region Flag:
    My next challenge relates to the wiring for the slaves. I have been running one slave at a time with no problem using the wiring indicated in the two pictures below. Since the two slaves are identical and part of a two sided corridor bracket, I would like to connect them together so that both activate upon impulse from the master. I have not had any luck with different wiring combinations. Given the terminals shown in the pictures (2C & Busbar on the master and C and M on the slaves), can anyone suggest the correct wiring combination to run both slaves? Maybe I do not have eouph power? Thanks.

    David
     

    Attached Files:

  29. harold bain

    harold bain Registered User
    NAWCC Member Deceased

    Nov 4, 2002
    40,850
    162
    63
    Male
    deceased
    Whitby, Ontario, Canada
    Country Flag:
    Region Flag:
    If you run them in parallel, both will get the same voltage. In series, the voltage is halved. In parallel, the draw (current) will double. A voltmeter should show if the voltage drops too low with a parallel connection due to the increased current requirement. This would indicate your power supply can't supply enough power for multiple slaves.
     
  30. David J

    David J Registered User

    Jul 27, 2001
    75
    0
    6
    Richmond, VA
    Country Flag:
    Region Flag:
    Harold - Can you explain how to connect the slaves in parallel given the terminals that I have? I have been connecting them in series with no luck. David
     
  31. harold bain

    harold bain Registered User
    NAWCC Member Deceased

    Nov 4, 2002
    40,850
    162
    63
    Male
    deceased
    Whitby, Ontario, Canada
    Country Flag:
    Region Flag:
    Use the two terminals your master clock wires are connected to. Run two wires from these terminals, and hook them to the same terminals on the next slave.
    attachment.jpg
     
    David J likes this.
  32. David J

    David J Registered User

    Jul 27, 2001
    75
    0
    6
    Richmond, VA
    Country Flag:
    Region Flag:
    Harold:

    SUCCESS. Thanks for your help. It seems strange that two slaves that both belong in the same corridor bracket would be wired in parallel, but it works.

    Also, I have determined that my program mechanism issue relates to the fact that the spring does not provide enough tension to fully advance the drum. I will remove the mechanism and tighten the spring.

    David
     
  33. harold bain

    harold bain Registered User
    NAWCC Member Deceased

    Nov 4, 2002
    40,850
    162
    63
    Male
    deceased
    Whitby, Ontario, Canada
    Country Flag:
    Region Flag:
    David, wiring in parallel provides the same voltage to each slave. In series, it cuts the voltage in half with two slaves, or in thirds with three slaves. So the slave would have to be rated at half the voltage (or 1/3) supplied to work in series.
     
  34. David J

    David J Registered User

    Jul 27, 2001
    75
    0
    6
    Richmond, VA
    Country Flag:
    Region Flag:
    Update:

    I took the program mechanism out of the case and cleaned it up and added a little tension to the spring that moves the drum forward. After installation, everything is working well, and the program drum advances the entire and intended distance. So, the tape stays on time.

    David
     
  35. David J

    David J Registered User

    Jul 27, 2001
    75
    0
    6
    Richmond, VA
    Country Flag:
    Region Flag:
    I found this newer vintage (1973, I think) Standard slave, and I am wondering if it can be wired to run with my master? I do not think so, but I thought I would ask the experts. Thanks.

    David
     

    Attached Files:

  36. harold bain

    harold bain Registered User
    NAWCC Member Deceased

    Nov 4, 2002
    40,850
    162
    63
    Male
    deceased
    Whitby, Ontario, Canada
    Country Flag:
    Region Flag:
    I don't think you will have the correction circuits needed for this one, David. It's 110 volts AC. But if you plug it in on time, it will keep good time.
     

Share This Page