Your application is very clear now. I recommend our HSUPA router. Please find more information from our website:
We can also talk by email if you can send your information to firstname.lastname@example.org .
Shenzhen Yinghua Technology Co.,Ltd
---Focusing On Wireless Communication
About the PTCRB certificate, I think I should explain like this. You know 3G router is embeded with 3G module. While these modules are made by Huawei, ZTE, Sierra, and so on. And they have applied all certificates(like CE, FCC, PTCRB). So you don't need to worry whether they can work with local carrier.
The device's module must be PTCRB certified, but the device/router must be certified as well. All 2G/3G carriers in the US require the device to be PTCRB certified. In addition, check with your carrier to see if they require carrier approval.
In general, your price point is low. The only prices I've seen at that level ($150) were cases where individual companies manufactured their own devices and their volumes were 100K+. As a point of reference for market prices, contact Sierra, CalAmp, and Cisco.
We have extensive experience in this field and are delivering M2M solutions using the Mitsubishi range of PLC's to industrial customers. We have developed function blocks and a driver for our SCADA system (Adroit) that deal with all the complex issues of communicating over cellular networks. The most important aspect being that you don't need a fixed IP for your PLC and can use any data contract. Your SCADA requires a fixed IP. In essence the PLC establishes connection to the SCADA whenever it gets a link, the link is maintained and there is very small amounts of data sent to tell the SCADA that the unit is on-line. Data can be sent by exception (alarms/events) and non-critical data simply fills a buffer and can be snt at various levels of fullness of that buffer. You can poll for data at anytime etc.
It will also work with any router although if you need to be able to program the PLC over the network you need the ability to establish a serial communications link. We have used the MR900 modem from eTung in China and this is working very well and meets your price point at around US$200. Moxa also have a router that will work and this is under trial.
The system works with the FX, L and Q Series of PLC's.
Hope this is of use.