Also this device can be referred to: T-4, T 4.
T4 ammeter shield compact one limiting with separate thermocouple a thermoelectric device with a direct-reading system, and is intended to measure the current in high frequency circuits.
Dimensions - 80×80×50 mm.
Accuracy class - 2,5.
Shaking and shock resistance.
T4 ammeters are used as transmitters antenna ammeters in stationary and movable type.
Contact thermocouples, depending on the measuring range are available in two types:
- T-1 for ammeters with measuring range up to 10 A, inclusive;
- T -2 for ammeters with measuring range of current over 10 A.
Frequency - from 0,3 MHz to 7,5 MHz.
Measurement range - 0,5 A; 1 A; 2 A; 3 A; 5 A; 10 A; 20 A; 30 A; 50 A.
The basic error of the instruments:
- at 50 Hz - no more than ±2,5% of the nominal value of the scale;
- at frequencies from 0,3 MHz to 7,5 MHz - no more than ±5%.
Dials are quadratic and compressed in its initial part.
Working part of the scale - from 20% to 100%.
Operating position - vertical and horizontal.
Meter case - sprayproof.
- ammeter T4 - 0,240 kg;
- thermocouple T-1 - 0,18 kg;
- thermocouple T-2 - 0,37 kg.
As metals forming a thermocouple type temperature sensors in T-1 and T-2 used gold-palladium alloys and platinum-iridium.
Operating conditions ammeters T4:
The ambient air temperature - from -40° C to +60° C.
Relative humidity - 98%.
Ammeter T4 produced in a plastic housing for recessed mounting. T4 meters must be installed on the non-iron panels.
Photos: Ammeter T4