How to make the phase indicator independently
For the work it was always necessary to be engaged in electric power metering devices (to remove power meters in actual fact), and it is frequent, accepting new accounting, found the problem, namely - the power meter had "self-feed", or "self-shift", i.e. at the disconnected loading the power meter had the small movement of the disk.
This phenomenon is observed with induction elektroschechik (SA4-I678, SA4U-I678, etc.), at connection phasing (the priority of phases) shall be observed. And here then the phase indicator was necessary to look for the device to bring order to accounting. Now stand on all objects electronic which do not react to phasing. Perhaps someone needs the phase indicator which can be made independently which scheme we bring to your attention.
The phase indicators of the induction I-517 or FU-2 type released by the industry work to similarly asynchronous electric motors.
However availability of the rotating parts does them difficult on the design and inconvenient in operation. The phase indicators based and on other principles are known.
The scheme of the simple phase indicator is shown in fig. 1. It allows to define the sequence of phases in three-phase power supply networks with the zero wire to which connect the device HTZ plug, and the XT1 and XT2 plugs connect to two of three phase wires.
Let's assume, tension attached to the XT1 plug lags behind on the phase on 120 ° tension on the XT2 plug. To this situation there correspond schedules in fig. 2.
Thanks to the VD1 diode Iuye current in the chain of the managing electrode of the thyristor of VS1 flows only during positive half-cycles of tension on the XT2 plug.
At the time of t1 when tension on the XT1 plug and the anode of the thyristor becomes positive, the last opens and remains open before the termination of the half-cycle (t2 moment).
The face value of the R1 resistor is chosen in such a way that the lamp of HL1 shines in full heat, signaling that the sequence of phases corresponds to marking of plugs (XT2 — "And", XT1 — "In", the phase which remained not connected — "With").
If phase wires are connected to the device upside-down ("And" — to XT1, "In" — to XT2), the phase of current of the managing electrode of the thyristor lags behind on 120 ° the phase of anode voltage. Now the thyristor opens at the moment and is closed at the time of t4.
Mean value of the current proceeding through HL1 lamp is much less, than in the previous case therefore it gleams very much or does not shine at all. Intervals during which through the lamp of HL1 current flows in fig. 2 are shaded.
As VS1 except specified on the scheme thyristors of T112-10-5, KU202N are suitable. The KD105V diode can be replaced with any of the KD209 series. HL1 — the glow lamp on 26 V, 0,12 A, however will approach also another with rated current not less current of deduction of the used thyristor.
It is only necessary to pick up the R1 resistor of the corresponding face value and power. The selection of the resistor will be required and if rated linear stress in network differs from 220 Century.
Parts of the phase indicator are mounted in the body from insulating material of the suitable sizes on which front panel the HT1-HTZ plugs and the boss with HL1 lamp are installed.
Industrial phase indicators:
- The phase indicator (phase monitor) microcontroller IF 517M (IF of 517 M) is intended for definition of alternation of the phases A, B, C in three-phase network of 380 V of the industrial frequency of 50 Hz.
- Is issued instead of I-517, FU-2 (I-517, FU 2).
- Temperature, °C: from-45 to +45.
- Humidity, %, at 25 °C: to 98.
- Rated voltage, In: 380.
- Indication of operating modes: LED.
- Internal power source: no.
- Length of bonding wires, m: not less than 0,5.
- Overall dimensions, mm: 160х55х16.
- Weight, kg: no more than 0,11.
Phase indicators EI 5001 are intended for definition of the order of alternation of phases in three-phase alternating current circuits.
- Provides definition of the order of alternation of phases in three-phase alternating current circuits at values of tension in the chain from 50 V up to 600 Century.
- Provides definition of the order of alternation of phases in three-phase alternating current circuits in frequency band from 40 Hz to 1000 Hz at values of tension, In:
- frequency band, Hz from 40 to 500: from 50 to 600;
- frequency band, Hz from 500 to 1000: from 200 to 600.
Also provides definition of the order of alternation of phases lasting inclusion no more than 3 sec. with the interval between inclusions not less than 30 sec.
The power consumed by the phase indicator does not exceed the following values at the tension:
- 50 To V and frequency of 50 Hz: 2 BA;
- 100 To V and frequency of 50 Hz: 7,5 BA;
- 100 To V and frequency of 500 Hz: 4 BA;
- 500 To V and frequency of 50 Hz: 200 BA.
Overall dimensions: 65х65х45 mm
Weight: 0,19 kgTop