Campbell 4-Channel Current/Voltage SDM-CVO4 User Manual
Summary of 4-Channel Current/Voltage SDM-CVO4
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Sdm-cvo4 4-channel current/voltage output module user guide issued: 13.3.08 copyright © 2001-2007 campbell scientific inc. Printed under licence by campbell scientific ltd. Csl 436.
Page 3: Guarantee
Guarantee this equipment is guaranteed against defects in materials and workmanship. This guarantee applies for twelve months from date of delivery. We will repair or replace products which prove to be defective during the guarantee period provided they are returned to us prepaid. The guarantee will...
Page 5: Contents
Contents 1. Introduction .................................................................. 1 2. Specifications .............................................................. 2 2.1 general specifications ..............................................................................2 2.2 output speci...
Page 6: Tables
Contents tables 4-1. Datalogger to sdm-cvo4 connections.................................................4 4-2. Switch position and addresses .............................................................10 6-1. Description of instruction 103 ..............................................................
Page 7: Output Module
Sdm-cvo4 4-channel current/voltage output module the sdm-cvo4 is a synchronously addressed datalogger peripheral designed to allow the datalogger to output variable voltage or current signals under program control. Figure 1. Sdm-cvo4 (shown without mounting brackets) 1. Introduction the sdm-cvo4 exp...
Page 8: 2. Specifications
Sdm-cvo4 4-channel current/voltage output module the sdm-cvo4 is a synchronously addressed datalogger peripheral. Datalogger control ports 1, 2 and 3 are used to address the sdm-cvo4 and send out data that defines the desired voltage/current output of each of the four channels. The output levels are...
Page 9: 2.2 Output Specifications
Instruction manual 2.2 output specifications voltage mode: range: 0 – 10,000 mv resolution: 2.5 mv maximum output current: 30 ma per channel. Minimum load current: 5 μ a if output a ccuracy (+23 ° c) ± 0.02% of set voltage, + ( ± 2.5 mv). A ccuracy (-25 to +50 ° c) ± 0.13% of set voltage, + ( ± 2.5 ...
Page 10: 3. Power Considerations
Sdm-cvo4 4-channel current/voltage output module 3. Power considerations the sdm-cvo4 power requirements are large compared to most campbell scientific products, especially when driving significant loads. Care must be taken to ensure that the power supply can cope with this higher demand. Alkaline b...
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Instruction manual insert a small screwdriver into either the top or front slot, as appropriate, and push to open the terminal spring. Strip any insulation from the wire to give 7 to 9 mm bare wire. Push the wire into the opening, and, while holding it in position, withdraw the screwdriver to releas...
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Sdm-cvo4 4-channel current/voltage output module 4.2 output device connections for each output channel there are four terminals which are labelled v o , id plus there are two ground ( ) connections per channel. The two ground terminals are internally connected; two are provided for convenience. 4.2....
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Instruction manual a) the remote device powers the loop, where, depending on the ground referencing requirements of that device, the connection can be as shown in the diagrams below: v+ remote voltage source +ve remote current input v- cvo4 + – i d or v+ cvo4 remote current input v- + i d b) the sdm...
Page 14: 4.3 Output Mode Setting
Sdm-cvo4 4-channel current/voltage output module 4.2.3 shield and ground connections it is generally advisable to used shielded (screened) cable when connecting the output to any remote system to reduce the chances of noise pickup. The shield will only be effective if it is connected to a good groun...
Page 15: 4.4 Sdm Address Setting
Instruction manual select channel(s) by fitting jumper (s) between appropriate terminals. (current mode only.) jumper shown fitted to ‘enable’ channel 4. Jumper shown fitted in the unconnected ‘stored’ position. Figure 4-3. Location of jumpers on circuit board do not store the jumpers between any ot...
Page 16: 4.5 Safety Considerations
Sdm-cvo4 4-channel current/voltage output module table 4-2. Switch position and addresses switch setting base 4 address 0 00 1 01 2 02 3 03 4 10 5 11 6 12 7 13 8 20 9 21 a 22 b 23 c 30 d 31 e 32 f 33 use a screwdriver to select address figure 4-4. Address selection switch the address switch has a he...
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Instruction manual where the sdm-cvo4 is going to be used in applications where the potential difference between the datalogger and the output terminals exceeds 50 v rms ac, 74 vdc then careful consideration has to be taken to ensure safe operation and compliance with local safety regulations. For s...
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Sdm-cvo4 4-channel current/voltage output module this device is at the low end of its tolerance band (±10%), combined with the normal tolerance of flash test devices, then the spark gap could fire during a 1500 vac flash test, which may cause an indication of failure. Testing at a slightly lower vol...
Page 19: 6. Datalogger Programming
Instruction manual compensated for. With the sdm-cvo4 as an excitation source, any drift in its output accuracy, or of the logger measurement accuracy, can result in a combination of those errors. It is worth investigating, therefore, the exact requirements of the sensors you wish to use. For instan...
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Sdm-cvo4 4-channel current/voltage output module range of -20 ° c to +50 ° c would be scaled so at -20c the output is 0 mv and at +50 ° c the output is 10000 mv. To do this with the sdm-cvo4 you would use the mathematical functions of the datalogger to calculate a scaled value in a new input locatio...
Page 21: 6.2 Edlog Program Examples
Instruction manual if the sdm-cvo4 loses power for any reason, when power is restored the outputs will return to the default ‘off’ state. This will be held until the datalogger runs instruction 103 again to update the output levels required. 6.2 edlog program examples the following program examples ...
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Sdm-cvo4 4-channel current/voltage output module 4: volt (se) (p1) 1: 1 reps 2: 32 50 mv, 50 hz reject, slow range 3: 3 se channel 4: 4 loc [ radiation ] 5: 100 mult 6: 0.0 offset ; now output data in the normal way to final storage 5: if time is (p92) 1: 0 minutes (seconds --) into a 2: 1 interval ...
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Instruction manual 7: -1666.67 b3 8: 10 a4 9: -5000 b4 ; now update the sdm-cvo4 with the information ; for the four channels 11: sdm-ao4 (p103) 1: 4 reps 2: 30 sdm address 3: 5 loc [ scldout_1 ] 6.2.2 restricted range current output modes (4-20 ma) when driving a system that requires a restricted c...
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Sdm-cvo4 4-channel current/voltage output module ; then set the value to –3000 13: z=f (p30) 1: -3000 f 2: 00 exponent of 10 3: 5 -- z loc [ scldout_1 ] 14: end (p95) 15: end (p95) ; now update the sdm-cvo4 with the information ; for the four channels 16: sdm-ao4 (p103) 1: 4 reps 2: 30 sdm address 3...
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Instruction manual ; wait 100 m it to power-on an s for d the outputs to stabilize ; you ma increase this dela y need to y if the sensors ; themselves ; have a power-on delay 3: excitation with delay (p22) 1: 1 ex channel 2: 0000 delay w/ex (units = 0.01 sec) 3: 10 delay after ex (units = 0.01 sec) ...
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Sdm-cvo4 4-channel current/voltage output module 6.3 crbasic sdmcvo4 instruction this instruction is used to control the sdm-cvo4 four channel current/voltage output device. Syntax sdmcvo4 ( cvo4source, cvo4reps, sdmaddress, cvo4mode ) remarks this instruction controls the sdm-cvo4, which outputs a ...
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Instruction manual be cycled on the device to return it to its default state. Otherwise, if 0 or 1 is entered it will be ignored and the device will remain in its last override state. Refer to section 4.2.2 for connection details. 6.4 sdm-cvo4 instruction example this program example is for a weathe...
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Sdm-cvo4 4-channel current/voltage output module endif ' scale the measurements for the sdm-cvo4 to output 0-10000 mv wsout = ws_ms*200 'ws: 0-50 m/s = 0-10000 mv wdout = wd_0_540 *18.59 'wd: 0-540 deg = 0-10000mv tempout= 100*(temp_c+40) 'temp: -40-60 deg c = 0-10000 mv rhout = rh *100 'rh: 0-100 %...
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