Based
on a PSD that senses minute movements or changes in height, the Z4D-AO1
commercial-grade micro-displacement sensor detects displacement changes down to
10 µm. The nominal sensing distance is 5.5 to 7.5 mm. Response time is 100 µsec.
The sensor, which is 25×23.5×20-mm high, produces a two-signal analog
output that is a function of where, rather than how much, light strikes the PSD
chip. Prices start at $45. Omron Control Components Division,
Schaumburg, IL. (708) 843-7900.
NTC
glass-encapsulated Uni-Chip thermistors come in resistance values ranging from 1
k(ohm) to 5 M(ohm) with resistance tolerances of 1% to 10% and accuracies to
within 1°C from 0 to 100°C. Housed in DO35 packages, the Uni-Chip
withstands temperatures from -60 to +300µC continuous. You can use the
devices in a range of temperature-control applications, including automotive,
medical, computer, communications, and aerospace equipment. Parts with 10%
resistance tolerance at 25µC cost $0.42 (5000). Fenwal Electronics Inc,
Milford, MA. (508) 478-6000.
This
family of photoelectric sensors minimizes the chance of false signals through
the use of a simple two-button setup procedure. The sensor measures signal
strength when a target is or is not present, thus automatically adjusting its
own switching point to provide maximum protection against false signals in both
states. You can use this automatic adjustment feature under dynamic operating
conditions, such as sensing targets on a moving conveyor line. The amplifiers
come with through-beam or reflective polymer fiber optics sheathed in polyamide.
The device costs $128, and fibers cost $40. IFM Efector Inc, Exton, PA.
(610) 524-2000.
Twelve
transducers, seven switches, and five gauges/indicators join the Mepcopal line
of pressure sensors. The devices work with noncorrosive gases and liquids;
double-diaphragm models accommodate gasoline and other SUS316 and 316L liquids.
Transducers have an amplifier option, and switches offer such features as an
LCD, dual pressure setpoints, and gauge, differential, or absolute sensing. From
$120. Philips Components, Jupiter, FL. (407) 745-3300.
Industrial
ac-operated LVDTs in the SQ series have measurement ranges from ±0.500 to ±5.000
in. Equipped with contactless moving elements for increased reliability, the
units are double-shielded internally for immunity to electrical noise. Each
device has a heavy aluminum housing, which is encapsulated in epoxy, suitable
for use in mill and outdoor-process environments. Electrical terminations are
made through barrier-type terminal strips. Prices range from $375 to $798. Macro
Sensors, Pennsauken, NJ. (609) 661-8000.
Used for coarse access and servo control of pickup heads in 3.5-in. optical disk drives, the S5730 position-sensitive detector has an active area of 24×0.7 mm and typically holds position-detection errors to within ±50 mm. Position resolution is typically 0.6 µm. The S5730 operates across a spectral response range of 320 to 1100 nm with a peak sensitivity wavelength of 960 nm. The device also has typical photosensitivity of 0.58 A/W at 960 nm and dark current of 1 nA at a reverse bias voltage of 5V. The detector, which is housed in a package that is 36.7×4.0 mm and is 1.36-mm thick, costs $16.55 (1000). Hamamatsu Corporation, Bridgewater, NJ. (908) 231-0960.
Operating in environments that encounter shocks of up to 5000g, the MSA series of micromachined servo accelerometers provides at least 500% greater shock survivability than comparable products. The devices offer 5-mg bias composite error, 2-µg resolution, and low-vibration rectification error. Both the MSA100 square- and MSA110 triangular-base accelerometers have a response range from dc to 500 Hz and a ±10V dc output with ±13 to ±18V dc excitation. Units operate over a temperature range of -65 to +221°F. The MSA 110 costs $1500 (25). Endevco Corp, San Juan Capistrano, CA. (714) 493-8181.