Panel Meter Specifications

[dilshan]

I check specifications of few AC Panel Meters (Ammeters). Under those specifications I'm confuse with following entry:

Measuring Range: 0-200/5A AC

What is the meaning of 0-200 and 5A?

(I check the dial of the panel meter and it seems like it can measure 0 - 200 Amps. but then, what is this 5A means?)

 

[aashitech]

Thats current ratio of CT (Current Transformer..its the sensor which sense the current flow)...it tells that at 200 Amps of input current will produce 5 Amps of secondary current (this secondary current is what one will route through a shunt resistor to ground...which will result in voltage development across this shunt resistor ..and that's the voltage the Panel meter actually measures)...
Above panel parameter indicates that this panel meter is suitable/meant for CTs ( Current Transformers) having 200:5 current ratio.

 

[dilshan]

Thats current ratio of CT (Current Transformer..its the sensor which sense the current flow)...it tells that at 200 Amps of input current will produce 5 Amps of secondary current (this secondary current is what one will route through a shunt resistor to ground...which will result in voltage development across this shunt resistor ..and that's the voltage the Panel meter actually measures)...
Above panel parameter indicates that this panel meter is suitable/meant for CTs ( Current Transformers) having 200:5 current ratio.

thanks for the info.

Can we use this sort of ammeter directly with circuit or we need to couple it via external shunt/CT ?

The model is some-what similar to this: https://tengenele.en.alibaba.com/product/550857333-213458428/AC_Ampere_Meter_100_5A.html. (Sorry, I can't find exact model from the internet. )

 

[aashitech]

thanks for the info.

Can we use this sort of ammeter directly with circuit or we need to couple it via external shunt/CT ?

The model is some-what similar to this: https://tengenele.en.alibaba.com/product/550857333-213458428/AC_Ampere_Meter_100_5A.html. (Sorry, I can't find exact model from the internet. )

As the manufacturer specifically indicated the C.T ratio so its obvious to me that some external C.T is required by this Panel meter.

EDIT :- i just saw the web link you posted..as its a analog moving coil type meter you can verify whether it contains any shunt/C.T by opening the housing . If the coil of meter is directly connected to meter`s external connection Lugs/connection Screws and nothing else is there then definitely this meter needs external Shunt/C.T...BUT if there is some sort of thick conductor wire or coil ( kind of Cheap non calibrated shunt) is attached across panel meters Lugs/connection Screws then no external Shunt/C.T is required...this is usually the case with cheap low quality ammeters.

 

[dilshan]

Thanks aashitech, I'll check this once I got the sample.