Remote Accessing
LAN based devices


This is decidedly an issue of "if you must" as the solution shown below is by no means ideal. However, if the limitations are acceptable then the following kit will allow extremely portable remote access to LAN based devices such as Power Recorders.

webramp on a power recorderThe heart of the remote access system is a Webramp 310e (middle front) which is effectively a LAN to WAN router with connection to external modems. The modem in this case is a Siemens M20T Terminal version GSM cellular modem (top right). Here the whole kit is connected to a Power Recorder from Reliable Power Meter (top left).

The reason the Webramp is chosen is it allows modems to be changed or added as technology in mobile data advances. At present GSM technology only allows for 9600 baud, just a little slower than the 56kb now available on fixed telephone lines!

The Webramp must be programmed via the console input. This is owing to the fact the Webramp default settings don't offer much movement with respect to IP addresses etc. Once the basic Network settings are complete and there is no possibility of changes causing broken paths, then final "tweaks" can be performed via the Internet Browser set-up screens.

There are a few basic rules about the SIM card: The SIM must not be password protected. Unfortunately this could lead to theft, or just simple abuse, but it must be remembered all outgoing calls can be traced and it would not take long to figure out who the guilty party is.

The card must also have a DATA number attached to it The data number is necessary to convert the analogue modem signals to digital, this done through special numbers at the service provider's switch. It is not necessary to have a fax number attached to the primary number but some provider's have both services through one number.

The M20 must be set for no echo and 57600 baud serial data rate. The Webramp appears to only operate at this speed with all modems from 33600 bps and lower.

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© 03.05.01