Lumel N30O User Manual

Also see for N30O: User manual User Manual & Quick Start

Contents

Lumel N30O User Manual Manual pdf 56 page image

10. PROGRAMMING EXAMPLESExample 1. Programming the meter to work with the flowmeter with reedrelay output of the following parameters:- pulse constant 1K - 4,3956 dm3/pulse = 0,0043956 m3/pulse;- minimal flow Qmin – 0,02 m 3/hThe parameters of input 1 should be set as follows:- tYP1 should be set to FreqL (frequency for (f<10kHz));The pulse constant for scaling should be given in m 3, but only fivesignificant digits can be set. When multiplying by a constant (SCAL setto AND), when rounded to five digits we get value 0.0044 (introducing tothe result of the calculation error of 0.1%). To reduce the error introdu-ced by the conversion, change the scaling by a constant dividing (SCALset to div) and as a constant value write the multiplicative inverse:ConS1= =227,5002275 ≈ 227,50When the inverse is rounded to five digits, the error introduced into thecalculations is of the size of 0.0001%.- SCAL1 should be set to dIv, ConS1 should be set to 227,50;- t_L1 and t_H1 should be set to a value 10 [ms] (due to the multiplicationof the pulse with a mechanical switch);- E-In1 – if no control inputs are used, should be set to bUt;To set the time, after which a zero flow will be indicated, the maximum timeinterval between pulses should be calculated for minimum flow Qmin.maximal time interval between pulses t_ max =t_ max =10,0043956pulse weight [m3] * 3600 [s]Qmin [m3]0,0043956 * 3600 [s]6