In the product parameter table, the total power is not written in the same form for every model. The ZYD-100 is written as 72 + 5 kW, the ZYD-300 as 110 + 11 kW, and the ZYD-200 as 175 kW with a note in brackets that 160 kW of this is heating. There look to be three different ways of writing it, but in fact they say the same thing: the electricity used by this machine is not a uniform load but is divided into several circuits that can be metered and controlled separately.
First, the most common misreading: 72 + 5 kW is not a range from 72 to 5 kW, and it is not two configurations of which one can be chosen. The distribution capacity on site is calculated from the sum of the two figures, so the installed capacity of the ZYD-100 is 77 kW; asking the supply side on the basis of the first figure alone understates the capacity, and both the wiring and the protection then have to be reworked.
Why the circuits are listed separately
Because the operating modes of these circuits are completely different. The heating circuit is switched according to the temperature control, the temperature control range being 45–80 °C, and with oil of a high water content the upper limit is pressed down to 70 °C: once the temperature is reached the heating stops, and if it is not reached the heating stays in; the pumping circuit and the vacuum circuit follow the process and run continuously, from the start of vacuum pumping to the end of degassing without stopping. Only by listing them separately can the site configure the circuits individually, meter them circuit by circuit, and separate in the energy consumption which part of the electricity went to the heating and which part went to the pumping.
The way the ZYD-200 is written shows the point most clearly: a total power of 175 kW, of which 160 kW is heating. This is a high-flow model, with a processing flow rate of 12000 L/h and a machine weight of 1950 kg. More than nine tenths of its electricity goes into heating the oil to the set temperature, and the pumping and the vacuum take only the small remaining share. Within the same series, the larger the flow rate and the larger the tank, the higher the proportion taken by the heating, because what the heating acts on is the whole quantity of oil in the tank, while the pumping and the vacuum follow the flow rate alone.
| Model | How the total power is written | What the two figures each refer to |
|---|---|---|
| ZYD-100 | 72 + 5 kW | The installed capacity is calculated from the total; do not take only the first figure |
| ZYD-300 | 110 + 11 kW | High-flow model; the capacity and the cable specification have to be prepared on the basis of the total |
| ZYD-200 | 175 kW (of which 160 kW is heating) | The heating proportion is high; the current surge on switching has to be checked separately |
Which figure the distribution step should follow
- The incoming supply capacity and the circuit breaker are prepared on the basis of the total. The power supply of the machine is three-phase 380V / 50Hz, and the margin in the incoming cable, the protective switch and the upstream distribution cabinet all has to cover the total plus the loads that are switched in at the same time.
- The heating circuit has to be considered separately for switching surges. The heating elements are switched in as a group according to the temperature control, the momentary current is higher than the steady-state value, and the wiring and the protective devices have to leave margin for this section.
- The protective devices are checked against the configuration fitted to the machine. Phase loss and phase sequence protection are part of the machine-side configuration; during the electrical acceptance on site, check their operating records. Voltage fluctuation and phase loss do not disappear by themselves because of a machine parameter.
- Ask before changing the supply conditions. When the machine is fed from a generator, or when the voltage level on site does not match three-phase 380V / 50Hz, the premise of 50 Hz no longer holds, and the way forward has to be confirmed before it is decided.
Breaking the energy down is the real purpose of listing the circuits separately
If only the total power is looked at, the account that comes out is only how much electricity this machine used in one month. With the circuits metered separately, more specific questions can be answered: how much the heating took, how much the pumping and the vacuum took, and how much of the electricity used per litre of oil brought up to standard has to go into the heating. This difference is far more useful than the total power when the purification cost and the modification scheme are being worked out.
Writing the total power as two figures is not a typographical habit; only separate circuits make it possible on site to work out the energy consumption and to select the right distribution.
