SIM card takes long time to connect (and only to GSM)



I’m currently resided in China. I just got the SIM card today and tested with SIM7000C and Quectel BC28 (and it only succeeded with SIM7000C). I noticed it takes about 1 hour to get connected (The “AT+COPS?” command returns the operator as shown below). And, it can only connected to GSM on China Unicom. (When I set to LTE only, it won’t connect)

I tested the “AT+COPS=?” command, it returns as follows:
+COPS: (1,“460 00”,“460 00”,“46000”,0),(1,“460 01”,“460 01”,“46001”,0),(1,“460 00”,“460 00”,“46000”,9),(1,“460 11”,“460 11”,“46011”,9),(0,1,2,3,4),(0,1,2)


Anyone has the same issue with the long connection time and GSM only? And any way to solve it?

Thanks and regards,


Hey Skyin,

Please look at this thread: SIM/Device re-registration duration


Hi Maiky,

I don’t think it is related to the network registration time. I tried SIM7000E in Singapore also (with a Singtel NB-IoT SIM card). The slowest registration time I have seen is less than 10 mins. An hour is definitely too long for that. And, I can’t connect to the LTE network.

I tried the Hologram SIM card on a botletics shield (with SIM7000G) here in China also, it has the same problem… It can find the LTE operators with the “AT+COPS=?” command, but unable to connect.


Hey Skyin,

In that case I am not sure. An hour is definitely way longer than anything I have seen before, but its curious that it connects after that. Normally in these situations I like to consult the devices documentation. An easy sanity check would be inserting your SIM into an unlocked phone just to make sure everything is set up properly.

Once you connect for the first time does it still take a long time to connect?