描述
用户可以用编程器读出RAM中的内容,也可以将用户程序写入RAM,因此RAM又叫读/写存储器。它是易失性的存储器,将它的电源断开后,储存的信息将会丢失。RAM的工作速度高,价格低,改写方便。为了在关断PLC外部电源后,保存RAM中的用户程序和某些数据(如计数器的计数值),为RAM配备了一个锂电池。现在有的PLC仍用RAM来储存用户程序。
1 Nortel BCM400 4.0 BCM 400 R4.0 R4 80vm MCDN Dual PS
Nortel / Alteon Aplication Switch EB1412026E5 AS 2424 E
Nortel Alteon 2424-SSL EB1412006 Application Switch
Nortel BCM 400 Rls 4.0 with Call Center + Cards
Nortel BCM 450 Voice Messaging 64 Seat Code NTC01022KC
Nortel PBX MICS 8 Line 20 T7316 Business Phone System!
Nortel 8630GBR 30Port SFP rout/sw DS1404063 8600
Nortel OPTera Metro OADM 5200 OC-48 NT0H50AA
Nortel Norstar MICS System 8×32 CI, CallPilot, T7316e
Nortel Norstar CICS System 4×16 CI, CallPilot, T7316e
40 Nortel I2004 NTDU82BA NTDU82 Icon Keys w PC PORT PS
Nortel Phone System Call Pilot Voicemail and 20 T7316E
Agilestar – AA1419071-E6 – For Nortel – New in Box
Nortel Business Phone System Package #7 w/ 1yr Warranty
NORTEL Alteon 2424 EB1412003 Application Switch
Nortel Promatory IMAS 1900 CSC 3302 3102 ADSL DMT SDSL