National Instruments NI 9235 manual

OPERATING INSTRUCTIONS AND S PECIFICATIONS NI 9235/9236 8-Channel, 24-Bit Quarter-Brid ge Analog Input Module ni.com/manuals Deutsch Français[...]

NI 9235/9236 2 ni.com This doc u ment describes ho w to u se the National Instr u ments 9235 and National Instr u ments 9236 and incl u des specif ications and terminal assignments. In t his doc u ment, the NI 9235 and NI 9236 are referred to incl u si v ely as the NI 9235/9236. V isit ni.com/info and enter rd s oftwarever s ion to determine which [...]

© National Instruments Co rp. 3 NI 9235/9236 Safety Guidelines Operate the NI 9235/9236 only as described in these operating instr u ctions. Hot Surface This icon denotes that the component may be hot. T o u ching this component may res u lt in bodily inj u ry . Safety Guidelines fo r Hazardous Loca tions The NI 9235/9236 is s u itable for u se in[...]

NI 9235/9236 4 ni.com Caution S u bstit u tion of components may impair s u itability for Class I, Division 2. Caution For Zone 2 applications, install the system in an enclos u re rated to at least IP 54 as defined b y IEC 60529 and EN 60529 . Caution For Zone 2 applications, connected signals m u st be within the following limit: Capacitance ....[...]

© National Instruments Co rp. 5 NI 9235/9236 Special Conditions fo r Marine Ap plications Some mod u les are Lloyd’ s Register (LR) T ype Approv ed for marine applications. T o verify Llo yd’ s Register cert if ication, visit ni.com/certification and search for the LR certificate, or look for the Lloyd’ s Register mark on the mod u le. Cauti[...]

NI 9235/9236 6 ni.com Connecting the NI 9235/9236 The NI 9235/9236 has a 24-terminal detachable spring-terminal connector that provides con nections for 8 analog inp u t channels. Figure 1. NI 9235/923 6 T erminal Assignmen ts EXC0 AI0 RC0 EXC2 AI2 RC2 EXC4 AI4 RC4 EXC6 AI6 RC6 EXC1 AI1 RC1 EXC3 AI3 RC3 EXC5 AI5 RC5 EXC7 AI7 RC7 1 2 3 4 5 6 7 8 9 1[...]

© National Instruments Co rp. 7 NI 9235/9236 Yo u can connect a q u arter- bridge sensor to each channel. Each channel has an EXC termi nal that pro vides the exc itation v oltage stim u l u s, an AI terminal tha t meas u res the bridge voltage, and an RC terminal that pro vides the q u arter -bridge completion. Refer to Fig u re 2 for an ill u st[...]

NI 9235/9236 8 ni.com Connecting Wires to the NI 9235/9236 Conn ector Use a flathead scre wdriv er with a blade smaller than 2.3 × 1.0 mm (0.09 × 0.04 in.) to connect wires to the detachable spring-terminal connector . Insert the screwdri ver in to a spring clamp activ ation slot and press a wire into th e corres ponding connector terminal, then [...]

© National Instruments Co rp. 9 NI 9235/9236 Wiring for High-Vib ration Applications If an application is s u bject to high vibrat ion, National Instr u ments recommends that yo u u se the NI 9965 backshell kit to protect the connections. Re fer to Fig u re 4 for an ill u stration of the NI 9965 connector backshell. Figure 4. NI 9965 Connector Bac[...]

NI 9235/9236 10 ni.com NI 9235/9236 Circuitry The NI 9235/9236 is isolated from earth gro u nd. Ho we ver , the individ u al channels are not isolated from ea ch other . The EXC terminals all co nnect internally to a comm on exc itation s u pply . Yo u m u st connect each EXC terminal to only one gage to maintain the channel-to-channel crosst alk p[...]

© National Instruments Co rp. 11 NI 9235/9236 Figure 5. Input Cir cuitry for One Channel of the NI 9235 EXC AI RC + – Bridge Completion Re s i s tor Filtered Differenti a l Amplifier 2.0 V Bridge Excit a tion 120 Ω 50 k Ω Sh u nt Re s i s tor + – ADC NI 9235[...]

NI 9235/9236 12 ni.com Figure 6. Input Cir cuitry for One Channel of the NI 9236 The NI 9235/9236 also incl u des filt ers to pre vent al iasing. The filters on the NI 9235/9236 f ilter according to the sampling rate. Refer to th e Understanding NI 9235/9236 Filtering section for more informatio n abo u t filte ring. EXC AI RC + – Bridge Completi[...]

© National Instruments Co rp. 13 NI 9235/9236 Q u arter -bridge meas u rements are inherently sensitiv e to acc u racy degradation d u e to the le ad resistance of wiring from the sensor to the meas u rement de vice. For a give n change in the gage resistance, the total ef fectiv e resistance cha nges slightly less. Accordingly , the meas u red mV[...]

NI 9235/9236 14 ni.com Sh u nt calibration sim u lates strain in p u t by changing the resistance of an arm in the bridge b y a known amo u nt. By sh u nting, or connecting, a large resistor across one arm of the bridge, a specif ic change occ u rs in the bridge v oltage ratio. W ith the connected sensor in a sta ble, typica lly u nloaded, state, y[...]

© National Instruments Co rp. 15 NI 9235/9236 Understanding NI 9235/9236 Filtering The NI 9235/9236 u ses a combination of analog and digital filte ring to pro vide an acc u rate representation of in-band signals while rejecting o u t-of-band signals. The filters di scriminate between signals based on the freq u ency range, or bandwidth, of the si[...]

NI 9235/9236 16 ni.com Figure 7. T ypical Passband Response for the NI 9235/9236 Fr e qu ency (kHz) 5 4 0.025 0.000 –0.025 –0.050 3 2 1 0 G a in (dB)[...]

© National Instruments Co rp. 17 NI 9235/9236 Stopband The filter signif icantly atten u ates all signals abo ve the stop band freq u ency . The primary goal of the filter is to pre vent aliasing. Therefore, the stopband freq u ency scales precisel y with the data rate. The stopband rejection is the minim u m amo u nt of att en u ation applied by [...]

NI 9235/9236 18 ni.com the mod u les m u st share a single master timebase so u rce. Refer to the software help for information abo u t conf ig u ring the master timebase so u rce for the NI 9235/9236. V isit ni.com/info and enter c s erie s doc for information abo u t C Series doc u mentation. The follo w ing eq u ation pro vides the av ailable da[...]

© National Instruments Co rp. 19 NI 9235/9236 Sleep Mode This mod u le s u pports a low-po wer sleep mode. S u pport for sleep mode at the system le vel depe nds on the chassis that the mod u le is pl u gged into. Refer to the chassis man u al for information abo u t s u pport for sleep mode. If the chassis s u pports sleep mode, refer to the soft[...]

NI 9235/9236 20 ni.com Specifications The follo wing specifications a re typical for the range – 40 to 70 °C u nless otherwise note d. The specifications are the same for the NI 9235 and the NI 9236 u nless otherwise noted. Input Characteristics N u mber of channels .................. ........ 8 a nalog inp u t channels Q u arter -bridge comple [...]

© National Instruments Co rp. 21 NI 9235/9236 Data rate range ( f s ) u sing internal master tim ebase Minim u m ...................... ........... ... 794 S/s Maxim u m ......... ......... ............ ..... 10 kS/s Data rate range ( f s ) u sing external master timebase Minim u m ...................... ......... ..... 195.3125 S/s Maxim u m ....[...]

NI 9235/9236 22 ni.com Acc u racy , NI 9235 Stability , NI 9235 Gain drift .. ........... ......... ........ 6 ppm/°C Offset drift ........... ......... ........ 2.2 μ V/V/°C Measurement Conditions Per cent of Reading * (Gain Error) Per cent of Range †, ‡ (Offset Error) 30 days after ca l. ( ±5 °C) 1y e a r after cal. ( ±5 °C) Calibrated[...]

© National Instruments Co rp. 23 NI 9235/9236 Acc u racy , NI 9236 Stability , NI 9236 Gain drift .. ........... ......... ........ 6 ppm/°C Offset drift ........... ......... ........ 1.7 μ V/V/°C Measurement Conditions Per cent of Reading * (Gain Error) Per cent of Range †, ‡ (Offset Error) 30 days after ca l. ( ±5 °C) 1y e a r after ca[...]

NI 9235/9236 24 ni.com Channel-to-channel ma tching (calibrated) Phase nonlineari ty f in = 0 to 1 kHz..... ........... ......... ... ±0.002° f in = 0 to 4 kHz..... ........... ........... . ±0.1° Inp u t delay .......... ........... ......... .......... 38.2/ f s + 11 μ s Passband Freq u ency ..... ......... ........... ......... . 0.45 · f [...]

© National Instruments Co rp. 25 NI 9235/9236 Alias-free bandwidth ..... ......... .......... 0.45 · f s Oversample rate ......... ......... ........... ... 64 · f s Rejection at o versa mple rate 1 (f s = 10 kS/s) ......... ........... ......... ........ 80 dB @ 640 kHz Inp u t noise f s = 1 kS/s NI 9235 ......... ........... ............ 0.38 [...]

NI 9235/9236 26 ni.com Crosstalk ( f in = 1 kHz) .......... ............ –100 dB Common-mode vo ltage, all signals to earth gro u nd ......... ........ ±60 VDC CMRR ( f in = 0 to 60 Hz) NI 9235 ........... ........... ............ ..... 120 dB NI 9236 ........... ........... ............ ..... 110 dB MTBF .......... ........... ............ ....[...]

© National Instruments Co rp. 27 NI 9235/9236 Shunt Calibration Characteristics Sh u nt calibration acc u rac y Resistance NI 9235 ........... ........... ............ ..... 50 k Ω NI 9236 ........... ........... ............ ..... 100 k Ω O u tp u t val u e NI 9235 ........... .................. .......... –599.28 μ V/V NI 9236 ........... .[...]

NI 9235/9236 28 ni.com Excitation Characteristics Excitation type .... ........... ......... .......... Consta nt voltage Excitation v al u e NI 9235 ......... ...................... ........ 2.0 V ± 1% NI 9236 ......... ...................... ........ 3.3 V ± 1% Maxim u m o u tp u t c u rrent NI 9235 ........... ........... ............ ..... 80[...]

© National Instruments Co rp. 29 NI 9235/9236 Thermal dissipation (at 70 °C) NI 9235 Activ e mode .... ........... .......... 735 mW max Sleep mode ........ ......... ......... . 2 5 μ W max NI 9236 Activ e mode .... ........... .......... 675 mW max Sleep mode ........ ......... ......... . 2 5 μ W max Physical Characteristics If yo u need to [...]

NI 9235/9236 30 ni.com Isolation Channel-to-channel ............ ........ None Channel-to-earth gro u nd Contin u o u s .... ........... ......... ... 60 VDC, Meas u rement Category I W i thstand ........ ........... ......... . 1,000 V rms , ve ri fi ed by a 5 s dielectric withstand test Meas u rement Cate gory I is for meas u rements performed on[...]

© National Instruments Co rp. 31 NI 9235/9236 Safety Standards This prod u ct is designed to meet the req u ire ments of the follo wing standards of safety for electrical eq u ipment for meas u rement, control, and laboratory u se: • IEC 61010-1, EN 61010-1 • UL 61010-1, CSA 61010-1 Note For UL and other safety certif ications, refer to the pr[...]

NI 9235/9236 32 ni.com Environmental National Instr u ments C Series mod u les are intend ed for indoor u se only b u t may be u sed o u tdoors if installed in a s u itabl e enclos u re. Refer to th e man u al for the chassis yo u are u sing for more information abo u t meeting th ese specif ications. Operating temperat u re (IEC 60068-2-1, IEC 600[...]

© National Instruments Co rp. 33 NI 9235/9236 Shock and Vibration T o meet these specif ications, yo u m u st panel mo u nt the system and u se the NI 9965 backshell to protect the connectio ns. Operating vibration Random (IEC 60068-2-64)......... 5 g rms , 10 to 500 Hz Sin u soidal (IEC 60068-2-6) ....... 5 g, 10 to 500 Hz Operating shock (IEC 60[...]

NI 9235/9236 34 ni.com Note For EMC compliance, operate this de vice with shielded cabling. CE Compliance This prod u ct meets the essent ial req u irem ents of app licable E u ropean directi ves, as amended for CE markings, as follo ws: • 2006/95/EC; Low-V oltage Directive (safety) • 2004/108/EC; Electromagneti c Compatibility Directive (EMC) [...]

© National Instruments Co rp. 35 NI 9235/9236 For additional en vironmental information, refer to the NI and the Environment W eb page at ni.com/environment . This page contains the en vironmental reg u lations and direct i ves with which NI complies, as well as othe r en vironmental information not incl u ded in this doc u ment. Waste Electrical [...]

NI 9235/9236 36 ni.com Calibration Yo u can obtain the calibration cert ificate and information abo u t calibration services for th e NI 9235/9236 at ni.com/ calibration . Calibration interval ............... ........... . 1 year Where to Go for Support The National Instr u ments W eb site is yo u r complete reso u rce for technical s u pport. At n[...]

© National Instruments Co rp. 37 NI 9235/9236 and follo w the calling instr u ctions or dial 512 795 8248. F or telephone s u pport o u tside the United Stat es, contact yo u r local branch off ice: A u stralia 1800 300 800, A u stria 43 662 457990-0, Belgi u m 32 (0) 2 757 0020, Brazil 55 11 3262 35 99, Canada 800 433 3488, China 86 21 5050 9800,[...]

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