7 Replies Latest reply: Jul 31, 2012 3:46 PM by mariaL RSS

Newbie seeking Module and Engineer recommendation


Hi all:


I am new to this forum and I am looking for some help.  I have been involved with a couple of guys in the development of a product for remote temperature monitoring.  The data requirements are minimal and the devices are not mobile (once installed).  One of the guys involved is an engineer who claimed he had a lot of experience in this field and designed a prototype for us.  We had many, many delays but after almost 20 months seemed to have worked out most of the issues through trial and error, etc.  As it turns out, most of these issues were "rookie" mistakes and could have been avoided by reading a few of the whitepapers on this site. 


Anyway, now that we have units which seem to be working pretty well, we are moving into the certification stage and it turns out the GSM/GPRS module we have based the design on is not PCTRB certified, which means we have to go back to the drawing board.  This is a HUGE *****-up and has caused me to lose faith in this engineer.


What I wanted to ask is the following:


1) Can anyone make recommendations for a low cost GSM/GPRS module with PTCRB certification?  We plan on transmitting small amounts of data (1K) 3 or 4 times per day.

2) Can anyone recommend either a freelance engineer or engineering company with this type of development experience?


I would like to get this project back on track as soon as possible.





  • Re: Newbie seeking Module and Engineer recommendation

    Hi Jim,


    Sorry to hear you've been struggling to get your product developed.  I've seen dozens of customers go through the same struggles, so don't feel bad.


    To answer your first question, first which operator are you planning to deploy on?  If the module isn't certified by the operator, that could be another challenge, as it could take 6 months and $250K+ to get the module certified with your operator.  Your operator may also not allow a 2G module and/or device.


    To see which modules are PTCRB certified, you can go to http://www.ptcrb.com/vendor/complete/complete_request.cfm?tab=Certified .  For 2G modules, Telit, u-blox, Simcom, Cinterion, and Sierra Wireless are the top players.  All have PTCRB and operator certified modules.  Make sure you ask them, even if they say so in the product documentation.


    For your second question, Connected Development and Spectrum Design are the 2 design/development consultants that come to mind.  When considering using a consultant, remember that you've spent 20+ months trying to figure it out by yourself.  The design consultants will likely have you completely certified in as little as 1-3 months, depending on the state of your current design.


    Last bit of advice.  Check for existing devices that may fit your needs.  If you don't have to reinvent the wheel...


    Good luck!


  • Re: Newbie seeking Module and Engineer recommendation



    I concur with Curtis in regards to Spectrum. I have used them in the past and have had a good experience.


    When choosing your modem I do not believe you will be able to have a 2G modem certified by any carrier that is not already PTCRB certified and I would not recommend using 2G and using 3G/4G instead. There are many whitepapers on the repurposing of the 2G network to 3G and 4G.




  • Re: Newbie seeking Module and Engineer recommendation

    Hi Jim,

    I concur with the above and want to say there is one more hurdle to consider.  On which network will you plan to ride?  There are network operators such as T-Mobile and M2M MVNO's who will permit 2G modules on their network, Wyless, Jasper Wireless, Raco Wireless.  If you would like to be on the AT&T network, please refer to their list of modules found at ATT.com/modules.


    If you would like to save some money on PTCRB you can eliminate the free space OTA performance test if you are a data-only devices with a removable antenna that is connected to the device through an RF transmission line (such as a coaxial cable) greater than 20 cm in length and not physically attached to the host device.  The no-testing-required justification document noted above shall include a vendor-provided list of recommended external
    antennas. The vendor shall also include this list in the product user manual.  This was quoted from the most recent PTCRB release of NAPRD 12_5.

    Much Success!


  • Re: Newbie seeking Module and Engineer recommendation

    Another design firm to consider is ClearConnex. Using their ClearLink platform you will be able to swap out modules with minimal impact to the software application you have already written. It already supports modules most leading module manufacturers. They are also a lot easier to contact...

  • Re: Newbie seeking Module and Engineer recommendation

    Hi James,


    Here is some information on a PTCRB certified Ethernet / Cellular router.


    IR791WH01: $799.00    RS232/485/1 Ethernet to GPRS VPN (IPSec/L2TP/PPTP/GRE) OpenVPN supported  




    Key Features:

    • -13~158




    1 RJ45

    GSM/GPRS/EDGE: 850/900/1800/1900MHz


    Support X.509 base64 CA



    LAN Interface


    1 RJ45 fixed port, 10/100 Mbps
    10M/100M Ethernet auto-adaptive MDI/MDI-X auto crossover

    Isolation Protection

    1. 1.5KV isolation protection

    •Serial Interface


    1 RS232 or 1 RS485 optional, baudrate: 1200-115200

    ESD Protection


    Serial protocol

    Transparent TCP, Virtual COM, Modbus RTU

    •Cellular WAN Interface

    Universal Cellular


    850/900/1800/1900/2100 MHz


    850/900/1800/1900 MHz





    •SIM Card

    SIM Card

    3V, flip SIM card, Anti-dismantlement



    Operation: -25~70(-13~158)
    Storage: -40~85


    5% ~ 95%, non-condensing


    Metal Shell, IP30



    Power Input

    12 to 48V DC, Industrial Terminal Block

    • EMC


    EN61000-4-2, level 4

    Surge Protection

    EN61000-4-5, level 3


    EN61000-4-4, Level 4


    EN61000-4-3, level 3


    EN61000-4-6, level 3

    Oscillatory Wave Immunity

    EN61000-4-12, level 3

    Variation Magnetic Field Immunity

    EN61000-4-8, level 5

    •Safety Certificate



    Electric Strength

    DC500V imposed on communication lines to ground and on power lines to ground, r

    Link Auto-recovery

    Built-in hardware watchdog, auto-recovery
    PPP link detection & auto-recovery
    ICMP heartbeat link detection & auto-recovery



    3G: 284399 hours
    2.5G: 351123 hours


    best regards,

    Maria Lemone

    ICP DAS USA, Inc.

    1-310-517-9888 ext 105