Red Lion GEMINI 2 - Manual (Page 4)

GENERAL DESCRIPTION
The Gemini is a two input, microprocessor-based device which offers the features
and performance of a single (GEM 1000)/dual (GEM 2000) level preset counter or
sample time, rate indicator. The 6-digit display features 0.56" LEDs with negative
sign and overflow indicators. The internal precision is maintained to 9 digits. The 20
mA Current Loop Option (Gemini 2000 only) makes possible remote or
computerized monitoring or control of the count, Presets and Scale Factor.
Flexibility and usefulness are insured through user programmability. With
simple front panel keystrokes and rear panel switch settings, any one of a number
of configurations can be selected. Once the selection is made, all or part of the
keyboard can be disabled to protect the settings and guarantee that no unwanted
changes can occur during the measurements. All set-up data is stored in
E 2 PROM, which will hold data for a minimum of 10 years without power.
Whenever the power comes on, the Gemini performs a series of internal
diagnostics to verify the integrity of the stored data. There is also a self-test mode
and an ever-present “watchdog” timer to prevent processor lockup.
The construction of the Gemini features a metal, die cast bezel for maximum
durability with high quality appearance. The sealed front panel meets NEMA
4/IP65 specifications for washdown and/or dust. Electrical connections are made
with removable, plug-in terminal strips at the rear of the unit. Clamp type
pressure plate terminals accept stripped #14 AWG wire without lugs.
As a counter, the Gemini can monitor bi-directional, unidirectional (totalizer),
or quadrature signals. It can double or (with quadrature) even quadruple the
resolution of the incoming signal. Counting modes also provide for
anti-coincidence applications. Both channels of count information are monitored
simultaneously, no counts are lost, and the final output can be chosen as the sum
or difference of the two input channels.
As a rate indicator, a variety of sampling times are available. Accurate to one
hundredth of a percent, the sampling time can be set as 1, 2, 5, 10, 20, or 50 seconds.
The preset level(s) can be selected to control an open collector output(s). The
optional Gemini plug-in relay board makes it easy to field upgrade your Gemini
to provide 5 amp, 240 VAC relay output(s). The output(s) are also programmable
and can be set for terminate at the “other” output start, “other” output end, at
reset or reset end, after time delay, or boundary.
Preset and reset behavior of the output(s) and display are completely
programmable. The preset(s) can have a value ranging from -999999 to +999999.
Decimal placement will be the same as the decimal placement on the input value.
Various reset modes can be selected: manual reset to zero or preset; automatic
reset to zero or preset; or automatic reset after time delay. The manual reset will
always override automatic reset, if it has been enabled.
The scale factor, moveable decimal point, dummy right hand zeros, leading
zero blanking, and decade divider capabilities of the Gemini permit complete
control of the Gemini display. These features provide easy conversion of input
signals to desired measurement units (feet to meters, etc.). The input values can
be multiplied by any number from -5.9999 to +5.9999 with the scale factor. The
addition of up to 3 dummy right hand zeroes gives an effective display
multiplication of 10, 100, or 1000. Similarly, the decade divider provides 1, 2, or
3 decades of prescaling.
SAFETY SUMMARY
All safety related regulations, local codes and instructions that appear in the
manual or on equipment must be observed to ensure personal safety and to
prevent damage to either the instrument or equipment connected to it. If
equipment is used in a manner not specified by the manufacturer, the protection
provided by the equipment may be impaired.
Do not use this unit to directly command motors, valves, or other actuators not
equipped with safeguards. To do so, can be potentially harmful to persons or
equipment in the event of a fault to the unit.
PROGRAMMING THE GEMINI
When your Gemini arrives from the factory, it has already been programmed
to function as a preset counter.
The personality, functions, and modes are then set by pressing the appropriate
keys. A function is defined by a two-digit code which appears on the left side of
the display. The mode of that function is shown as a one-digit code on the right
side of the display. At times there will be a (-) sign modifier.
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