How to test SCR Module
SCR / THYRISTOR MODULE is a power electronic device which is for high current and high voltage application. It still use multimeter to test its condition : good or bad. The step to check is almost the same as small SCR and same principle , however , there is some difference in detail , for example we can not use multimeter to trig gate of SCR because it is a power electronic device. There are many model of SCR module in the market. On its name plate there is internal circuit diagram that is useful to check and installation.
The example SCR module consist of 1 SCR and 1 Diode.
How to check electronic device
---------------------------------------------------
Choose these articles to read more of device testing.
-------------------------------------------------
Step to check SCR / THYRISTOR MODULE with multimeter
1. Find the terminal and internal circuit diagram of SCR from its name plate or datasheet.
2. From the example SCR module consist of 1 SCR and 1 Diode. Check diode firstly by using Diode check range on digital multimeter. The good diode will present forward voltage drop 0.3-0.7V ( forward bias) and display OL 1 time when reverse bias. Shorted diode display 000V 2 time and Open diode display OL 2 time. If diode is already bad , no need to do the next step.
Check diode of THYRISTOR MODULE
Forward bias to diode , there is 0.371V forward voltage drop . = good diode
Reverse bias to diode , display " OL " = good diode
3. Check SCR condition , A and K1 terminal. Set to Ohm meter range , good SCR will display very high resistance as Mega Ohm. Shorted SCR , multimeter display 0 Ohm and Open SCR , multimeter display OL.
Check A and K1 terminal of SCR , good SCR get very high resistance Mega Ohm.
Check A and K1 terminal of SCR , good SCR get very high resistance Mega Ohm.
4. Check SCR condition , G1 and K1 terminal. Set to Ohm range on digital multimeter , good SCR will display low resistance . Shorted SCR , multimeter display 0 Ohm and Open SCR , multimeter display OL.
Check G1 and K1 terminal. , good SCR will display low resistance .
Check G1 and K1 terminal. , good SCR will display low resistance .
Analog multimeter can check diode on SCR module too if it is a good diode will point at low resistance when forward biasing and point at ∞ (Infinity) Ohm when reverse biasing. Check G1 and K1 terminal of SCR module , good SCR will display low resistance so it can check by Rx1 Ohm Range. However , A and K1 terminal of SCR is 4-5 Mega Ohm resistance analog multimeter can not display or present any pointer movement this is very high value , after try with the same module and same condition , it always point at point at ∞ (Infinity) Ohm.
