Thermo Scientific Micro-Tech 9101, Справочное руководство

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Thermo Fisher Scientific Micro-Tech 9101/9201 Reference Manual, Rev J A-33
Load-cell sense is controlled by selectable jumpers (J14 and J15 for
channel 1, and J19 and J20 for channel 2) located on the motherboard
and by jumpers (J2 and J3) on the Premium A/D Board. The jumpers
should be in position “1-2” local sense, if the distance is less than 200
feet between the load cell and the Micro-Tech. For distances greater than
200 feet and less than 3,000 feet, the jumper should be in position “2-3”
and a special 6-wire cable is required. Refer to the field wiring diagram
that is appended to this manual, for jumper requirement in the scale
junction box.
Table A–2. Motherboard Load-Cell Technical Specifications
(Model 9101)
Load Cell Excitation Power Supply 5 VDC ±10%, 90 mA, minimum load impedance (58 ohms).
Output short circuit, 0.5 A maximum.
Load Cell
Load cell input circuits
(2 each)
Number: Up to six (6) 350-ohm load cells in parallel. Cable
distance: 200ft [61m] or less without sense, or 3000ft [914m]
with sense.
Sensitivity: 0.5mV/V to 3.5 mV/V (keypad selectable).
Input Impedance: 1M-ohm minimum.
Maximum Usable Signal: 114% of 3mV/V.
Internal A/D counts: (3mV/V): 6,440,000.
Isolation: Non-isolated.
Max non-destructive input voltage: ± 6 V relative to ground.
Load Cell Cable Shield: Connected to earth ground.
Load Cell
Excitation-Sense Circuitry
(2 each)
4 wire system: cable distance not exceed 200ft [61m].
6 wire system: cable distance not to exceed 3000ft [914m].
Nominal input voltage: 5 VDC.
Input impedance: 100 k-ohm minimum.
Jumper selectable: Local or remote sense.
A/D Jumpers—
Load-Cell Sense
Load-Cell
Specifications