ZX25A switch type DC standard resistance box

1ZX25A switch type DC standard resistance boxStructure of resistance box

A resistance box is a variable resistance measuring tool, whose resistance value can be changed in a certain step within a known range. The resistance elements of the switch type DC standard resistance box are all connected between the contacts, and the contact brushes fixed to the rotating frame move on the contacts. The resistor used in this type of resistance box is the resistance between the starting contact and the contact touched by the brush during use.

IIZX25A switch type DC standard resistance boxPurpose:

Used for precise adjustment of resistors in DC circuits.
Resistance box for whole machine calibration below one thousandth
Using a precision resistance box to calibrate portable DC single bridge and other equipment

Main technical indicators of resistance box

Measurement range: 0.01---11111.1 ohms
When following the following usage conditions, the error of the resistance box will not exceed the basic error allowed in Table 1.

The ambient air temperature is 20- ± 3 ℃, and the relative humidity is below 80%;
The current is direct current;
The power shall not exceed the rated value.

3. The basic error of the resistance box is specified in Table 1:

• The insulation resistance between the internal circuit of the resistance box and the outer shell should not be less than 1000 megaohms, and the experimental voltage is 500 volts
• The insulation strength between the resistance box circuit and the casing must be able to withstand the effect of a 50 cycle frequency and an actual sine wave of 2000 volts AC for one minute.
• The maximum allowable current between each gear of the resistance box should not exceed the specifications in Table 2

7. The external dimensions are 340X165X148mm and the weight is approximately 4kg