Project
reference mark to gauge if the rotor always droops to the
same side. If one side is heavier than the other, trim a little
off the edge of the rotor that always dips until a reasonable
balance is achieved.
The coil assembly is positioned on the base plate so
that the rotor passes fully between the pole pieces. The
rotor height must be adjusted so that the rotor will spin
freely through the pole faces without touching them.
When you are sure of the positioning, place some epoxy
on the base and locate the coil assembly permanently.
Again, be sure the surfaces to be glued are roughened
and clean.
Once the coil assembly is secured to the base, the
coils may be wired. A thin, 18 gauge appliance cord can
be used to supply power. Because the top coil is driven out
of phase with the lower coil, the line is connected to pin 7
of the lower coil and pin 8 of the upper coil. Similarly, the
neutral is connected to pin 8 of the lower coil and pin 7 of
the upper coil.
Because the top coil is turned over from the position
of the lower coil, pin 7 of the lower coil is on the same side
of pin 8 of the upper coil. The electrical connections
should be insulated with silicon rubber sealant placed over
all exposed connections. While the motor draws little
power, it is connected to 120 VAC and deserves respect.
For safety — if a metal base is employed — the base should
also be electrically grounded through a three-pronged
plug.
When the coils are energized, the rotor will spin in the
direction of the shaded pole (the shaded pole lags the
main field). The rotor speed is about 20 RPM. Very little
torque is developed by this design, since the electrons can
slip within the aluminum rotor. The 1/16” aluminum rotor
is heavy enough that a light wind should not bother the
operation. Thinner, lighter rotors will require shielding from
air currents. An acrylic hemisphere for displaying models
or the bottom third of a plastic 2 L soft drink bottle can
provide a suitable cover.
The cover for this model was fabricated from a sheet
of 0.020” Lexan (polycarbonate) that I had available. The
3” diameter top circle and lower circular ring were scribed
with a compass and cut out with a pair of scissors. These
circular pieces are used to form the 2” tall strip into a
circular tube. The seams were glued with a solvent cement
supplied by McMaster Carr Supply Company (www.
mcmaster.com), part number 7528A13. The top has a
support hanging down that is terminated about 1/16”
above the top of the brass bearing to prevent the rotor
from coming off the pivot pin if the motor is jostled around
at your next science fair. NV
SAELIG BRINGS YOU EASY-TO-USE SOLUTIONS!
F
o
r
E
l
e
c
t
r
o
n
i
c
s
NUTS & VOLTS
E
v
e
r
y
t
h
i
n
g
USB in one IC!
USB<>RS485
USB Logic Analyzer
easyRADIO
USB Bus Analyzers USB-Serial Adapter
FT232BM Single chip USB-232 USB-COMi (non-isolated) or ANT8 Matchbox-sized USB- easyRADIO TM ER900TRS Tracker 110/Explorer 200high- Serial port for laptops without
solution with Windows/Mac/Linux USB-COMiSI (isolated) offer self- powered logic analyzer. Sample Transceiver Modules make performance, economical USB one! US232B instantly updates
drivers. No programming/USB powered USB to RS485 conver- 8 channels at up to 500 MS/s. wireless data transmission sim- 1.1/2.0 protocol analyzers. older RS232 products to USB!
knowledge required! Easiest sion with baud rates 184bps - View traces on PC. Print or ple for USA and Europe! Add Perfect for troubleshooting USB, PC thinks it’s using COMport
answer to update RS232 3Mbps. PC thinks it’s talking to a save for later review! (16-ch. wireless capability to your proj- optimizing data flow and USB but uses the USB connection.
devices! Only $2.55 (10k) COMport! only $48/$85! ver. too!) only $222! ect today! from $155! training! Only $899/$2700! Only $39 (1) or $29 (100)
CANbus Cards Industrial PCs Mini Web Server PC Scope Adapter RS232<>422/485 I2C for PCs
CANbus - Starter Packs and ATXRuggedized Industrial PCs PicoServTM Miniature Web K2 9p-9p self-pwrd RS-422/485 PCI93LV: industry-standard I2C
cards for almost any board format for guaranteed long production Server allows remote I/O and STINGRAY- 1 MS/s sampling K3 9p-9p isolated RS-422/485 card for PCs. WINI2C/PCI soft-
& OS. CAN/Ethernet bridges, life, economy, reliability. AMD servicing. Collect analog & 12-bit 2-ch USB scope adapter K3-232 9p-9p isolated RS232 ware gives windows-interface to
industrial automation solutions digital data over a web for PC. Looks like a “Digital developanddebug I2Cbussys- Athlon XP1700, shock-mounted connection. Remote sens- Scope” on your PC screen! K232-ISOL25p -25p RS232 tems. UCA93LV is new USB
from Janz AG as used by top 40GB hard drive. 100% Burn- ing/control, SCADA, building Great for laptops, and servicing. KD485-STD DINrail - isolated version. NOW! - transparently
companies all over the world. in. CE EMC. only $899 control, etc. from $189 DS1M12 only $189 KD485-PROG programmable! monitor at 400kHz! only $499!
Power Supply Dataloggers PC Scope Adapters BASIC modules Crystals / Oscillators SM PCB Adapters
• 1.5 to 30V d.c. output
• 0 to 1A output current
• 100 to 240 V a.c. input
• Over-volt/current &
short circuit protection
$79!
TDS2020F makes a custom CF ADC-212/100 turns your PC Tigers - tiny multitasking BASIC Euroquartz - Europe’s largest mfr OM-Adapt SM miniboards
card A/D datalogger or con- into a great high-speed scope. modules for quick projects. of quartz crystals, oscillators, filters have two footprints on either
troller - quickly! High-level Sampling to 100MS/s at 12-bit >100, 000 instr’s/s! i COM200 and frequency products. Custom fil- side. Now use your ultra fine pitch
software completes projects in res’n. FREE s/w turns PC into ready-made controller with LCD ters, high rel. rad tol. oscillators. SMD components with more
hours. Store GPS/CANbus/A or D powerful 2-ch scope, DVM & and keypad. Touch240controller Novel EQ-HM spread-spectrum useful 0.1" inline spaced holes.
data to card. only $199 ( 50 qty) spectrum analyzer. $95 - $1145 - with touchpad and LCD display. osc’s reduce EMI problems One-to-one pinouts. $6.99
Saelig Co. Inc.
ph 585-385-1750 fx 585-385-1768
www.saelig.com/ad/nv11.htm • info@saelig.com
Customer Comment of the month: “Impressive
response! Nice and clear...seems like your company
has a “can do” attitude. In today’s world, good
customer service is becoming scarce.” (P.A.)
Saelig Co. brings to USA unique, easy-to-use control and
instrumentation products from overseas. Customers include:
Intel, Philips, NEC, Kodak, Nokia, US Military, Microsoft,
Dell, Xerox, Universities, T.I., Harris, Sony, J&J,
Thomson, Sandisk, General Dynamics, H-P/Compaq, etc.
40
JANUARY 2005