Yaskawa iQpump Controller User Manual - Manual (Page 242)

242 YASKAWA TM.iQp.06 iQpump Controller User Manual
G.3 Well Draw Down Function
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3. Connect Level Transducer to the iQpump Drive
Most depth level transducers provide a 4 ~ 20 mA current signal. The A1 Terminal of the iQpump drive is calibrated for voltage-based
feedback at 0 ~ 10 Vdc. Installing a burden resistor simplifies the process of converting the current-based feedback to voltage-based
feedback.
The burden resistor should be 250 Ohms rated for a minimum of 1/4 W and a tolerance range of less than or equal to 1%. It is possible to
use different Ohm values if a burden resistor of exactly 250 Ohms is not available, however the gain and bias settings of the iQpump
drive must be adjusted accordingly.
Resistors can be purchased at most electronic stores, online, or through catalogues. Locate the necessary resistor value in Table G.2
below and match that to the correct gain (H3-02) and bias (H3-03) setting for that value.
Table G.2 Resistor Values and Gain/Bias Settings
The burden resistor is installed onto drive Terminal A1 to AC (analog common) see Figure G.3 .
Gain Setting Bias Setting Gain Setting Bias Setting
Ohms H3-02 H3-03 Ohms H3-02 H3-03
230 251.4% -27.2% 250 231.3% -25.0%
231 250.3% -27.1% 251 230.3% -24.9%
232 249.2% -26.9% 252 229.4% -24.8%
233 248.1% -26.8% 253 228.5% -24.7%
234 247.1% -26.7% 254 227.6% -24.6%
235 246.0% -26.6% 255 226.7% -24.5%
236 245.0% -26.5% 256 225.8% -24.4%
237 243.9% -26.4% 257 225.0% -24.3%
238 242.9% -26.3% 258 224.1% -24.2%
239 241.9% -26.2% 259 223.2% -24.1%
240 240.9% -26.0% 260 222.4% -24.0%
241 239.9% -25.9% 261 221.5% -23.9%
242 238.9% -25.8% 262 220.7% -23.9%
243 237.9% -25.7% 263 219.8% -23.8%
244 236.9% -25.6% 264 219.0% -23.7%
245 236.0% -25.5% 265 218.2% -23.6%
246 235.0% -25.4% 266 217.3% -23.5%
247 234.1% -25.3% 267 216.5% -23.4%
248 233.1% -25.2% 268 215.7% -23.3%
249 232.2% -25.1% 269 214.9% -23.2%
This table is valid for 4-20 mA feedback devices only.
Use 1/4 W resistors with a tolerance of 1%.