Keithley 2700, Service Manual

Page: 124 / 174

A-4 Specifications
DC MEASUREMENT CHARACTERISTICS
DC Volts
A-D LINEARITY: 2.0 ppm of r 1.0 ppm of range.
INPUT IMPEDANCE:
100mV–10V Ranges: Selectable >10G
Ω
// with <400pF or 10M
Ω
±1%.
100V, 1000V Ranges: 10M
Ω
±1%.
INPUT BIAS CURRENT: <75pA at 23°C.
COMMON MODE CURRENT: <500nApp at 50Hz or 60 Hz.
AUTOZERO ERROR: Add ±(2ppm of range error + 5µV) for < 10 minutes and ±1°C.
INPUT PROTECTION: 1000V, all ranges. 300V with plug in modules.
Resistance
MAX 4W
Ω
LEAD RESISTANCE: 10% of range per lead for 100
Ω
and 1k
Ω
ranges; 1k
Ω
per lead for all other ranges.
OFFSET COMPENSATION: Selectable on 4W
Ω
100
Ω
, 1k
Ω
, and 10k
Ω
ranges.
CONTINUITY THRESHOLD: Adjustable 1 to 1000
Ω
INPUT PROTECTION: 1000V, all Source Inputs, 350V Sense Inputs. 300V with plug-in modules.
DC Current
SHUNT RESISTORS: 100mA–3A, 0.1
Ω
. 20mA, 5
Ω
.
INPUT PROTECTION: 3A, 250V fuse.
Thermocouples
CONVERSION: ITS-90.
REFERENCE JUNCTION: Internal, External, or Simulated (Fixed).
OPEN CIRCUIT CHECK: Selectable per channel. Open >12k
Ω
.
EARTH ISOLATION: 500V peak, >10G
Ω
and <150pF any terminal to chassis.
DC Notes
1. 20% overrange except on 1000V and 3A.
2. Add the following to “ppm of range” uncertainty; 100mV 15ppm, 1V and 100V 2ppm, 100
Ω
30ppm, <1M
Ω
2ppm, 10mA and 1A 10ppm, 100mA 40ppm.
3. ±2% (measured with 10M
Ω
input resistance DMM, >10G
Ω
DMM on 10M
Ω
and 100M
Ω
ranges).
4. Relative to calibration accuracy.
5. For signal levels >500V, add 0.02ppm/V uncertainty for portion exceeding 500V.
6. Specifications are for 4-wire
Ω
, 100
Ω
with offset compensation on. With offset compensation on, OPEN CKT. VOLTAGE is 12.8V. For 2-wire
Ω
add 1
Ω
addi-
tional uncertainty.
7. Must have 10% matching of lead resistance in Input HI and LO.
8. Add the following to “ppm of reading” uncertainty when using plug in modules: 10M
Ω
220ppm, 100M
Ω
2200ppm. For Model 7703, add the following:
10k
Ω
10ppm; 100k
Ω
100ppm; 1M
Ω
1000ppm; 10M
Ω
1%; 100M
Ω
10% for <40% R.H. operating environment.
9. Add 1V when used with plug in modules.
10. For RATIO, DCV only. For AVERAGE, DCV and Thermocouples only. Available with plug in modules only.
11. Add 6µV to “of range” uncertainty when using Model 7703.
12. Auto zero off.
13. For LSYNC On, line frequency ±0.1 %. For LSYNC Off, use 60dB for
≥
1PLC.
14. For 1k
Ω
unbalance in LO lead. AC CMRR is 70dB.
15. Speeds are for 60Hz (50Hz) operation using factory defaults operating conditions (*RST). Autorange off, Display off, Limits off, Trigger delay=0.
16. Speeds include measurements and binary data transfer out the GPIB.
17. Sample count = 1024, auto zero off.
18. Auto zero off, NPLC = 0.01.
19. Add ±0.5°C uncertainty for type J, K, N, T, and E for temperatures <–100°C, for types R and S <+400°C, and for type B <+1100°C. Guaranteed by design for
types B, E, N, R, and S.