Just unpacked a new (been in its box in a couple of years) SMPS800RE from Connex.
I have mounted it in the chassis, connected earth on primary side to chassis and took some resistance measurements. (no other component connected)
Primary side: inf ohm between -v, gnd and +v
AUX1 and 2: inf ohm.
Secondary side:
Earth-ground and -v: 5k+*
Earth-ground and +v: 5k+ *
GND and -v: 2k+ *
GND and earth-ground: 4.65k (exactly)
-v and +v: 5k+
Primary earth and secondary -v: 6k+ *
Primary earth and secondary +v: 6k+ *
Primary earth and secondary earth: 4.65k (exactly)
Primary -v and secondary -v, gnd, +v: no connection
Primary +v and secondary -v, gnd and +v: no connection
* The numbers increase to about 15.5k ohm in a timeframe of 15seconds.
Is this how it is supposed to be? I was expecting to not get any resistance readings, being there should not be any measurable connection?
I have mounted it in the chassis, connected earth on primary side to chassis and took some resistance measurements. (no other component connected)
Primary side: inf ohm between -v, gnd and +v
AUX1 and 2: inf ohm.
Secondary side:
Earth-ground and -v: 5k+*
Earth-ground and +v: 5k+ *
GND and -v: 2k+ *
GND and earth-ground: 4.65k (exactly)
-v and +v: 5k+
Primary earth and secondary -v: 6k+ *
Primary earth and secondary +v: 6k+ *
Primary earth and secondary earth: 4.65k (exactly)
Primary -v and secondary -v, gnd, +v: no connection
Primary +v and secondary -v, gnd and +v: no connection
* The numbers increase to about 15.5k ohm in a timeframe of 15seconds.
Is this how it is supposed to be? I was expecting to not get any resistance readings, being there should not be any measurable connection?
Just unpacked a new (been in its box in a couple of years) SMPS800RE from Connex.....................................
If you use PostNord it may take a while for delivery. However, "a couple of years" is in the high end.😀
* The numbers increase to about 15.5k ohm in a timeframe of 15seconds.
Is this how it is supposed to be? I was expecting to not get any resistance readings, being there should not be any measurable connection
When you get impedance readings that steadily increase for a while it is because you are charging a capacitor with your measuring current. That is no problem.
SMPS may include resistors on the secondary side that you will notice when you measure impedance on the secondary terminals.
I do not have that particular SMPS but I have spotted nothing I see as problematic.
Perhaps a set of last measurements from all primary terminals and to earth-ground. You must get "inf".
If you use PostNord it may take a while for delivery. However, "a couple of years" is in the high end.😀
* The numbers increase to about 15.5k ohm in a timeframe of 15seconds.
Is this how it is supposed to be? I was expecting to not get any resistance readings, being there should not be any measurable connection
When you get impedance readings that steadily increase for a while it is because you are charging a capacitor with your measuring current. That is no problem.
SMPS may include resistors on the secondary side that you will notice when you measure impedance on the secondary terminals.
I do not have that particular SMPS but I have spotted nothing I see as problematic.
Perhaps a set of last measurements from all primary terminals and to earth-ground. You must get "inf".
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There's no "infinity ohms". For line to secondary you should normally get more than the 2Meg limit of common meters.
All the DC outputs will have capacitors, and can have voltage-dividers or (in-)active devices hanging on them. A truly "very high" reading would be unlikely.
All the DC outputs will have capacitors, and can have voltage-dividers or (in-)active devices hanging on them. A truly "very high" reading would be unlikely.
