Help Needed: Interfacing Saral 100 Energy Meter with Microcontroller via RS232

By Naman_Shandilya , 23 July, 2026
Forums
Gurux.Serial

Hi everyone,

I am new to the DLMS and energy meter domain. I am working on interfacing a Saral 100 energy meter (Secure Meters) with my microcontroller over the RS232 protocol. I’ve received some initial details from the vendor, but I want to confirm what exact parameters and values are required from the manufacturer to ensure proper communication and data reading.

Here’s what I have so far:

Voltage Levels – RS232 standard voltage levels (3–5 V depending on signal type).

Serial Communication Settings – Baud rate: 9600 bps, Parity: None, Stop bits: 1.

Authentication – KDF04 required.

Encryption/Security Keys – HLS keys.

Client and Server Addresses – Need confirmation of exact values.

Supported OBIS Codes – As per IS 15959 and manufacturer‑specific codes.

Sample Request‑Response Logs – One sample already received.

Communication Protocol – IS 15959.

My Question:
Could you please guide me on what additional parameters or values I should request from the meter vendor/manufacturer to successfully interface the Saral 100 with my microcontroller and read all required data?

Any advice, examples, or best practices from your experience with Secure meters and DLMS would be greatly appreciated.

Thanks in advance!

Naman_Shandilya

1 month 2 weeks ago

Hi Mikko,

Thanks for your response.
While interfacing Saral Meter with Gurux DLMS director i am getting echoing back the data which Gurux DLMS Director is Transmitting

I am getting this

13:58:02 01:58:02.374 Info Opening
13:58:02 01:58:02.374 Info Serial Port Settings: Port Name: COM24 Baud Rate: 9600 Data Bits: 8 Parity: None Stop Bits: One Flow Control: None Eop: None
13:58:02 01:58:02.377 Info Open
13:58:03 Send SNRM request.
TX: 7E A0 07 03 41 93 5A 64 7E
13:58:03 01:58:03.392 Sent 7E A0 07 03 41 93 5A 64 7E
13:58:03 01:58:03.404 Received 7E A0 07 03 41 93 5A 64 7E
13:58:08 Data send failed. Try to resend 1/3
13:58:08 01:58:08.406 Sent 7E A0 07 03 41 93 5A 64 7E
13:58:08 01:58:08.417 Received 7E A0 07 03 41 93 5A 64 7E
13:58:13 Data send failed. Try to resend 2/3
13:58:13 01:58:13.421 Sent 7E A0 07 03 41 93 5A 64 7E
13:58:13 01:58:13.429 Received 7E A0 07 03 41 93 5A 64 7E
13:58:18 Data send failed. Try to resend 3/3
13:58:18 01:58:18.440 Sent 7E A0 07 03 41 93 5A 64 7E
13:58:18 01:58:18.440 Received 7E A0 07 03 41 93 5A 64 7E
13:58:23 Failed to receive reply from the device in given time.
13:58:23 Send Disconnect request.
TX: 7E A0 07 03 41 53 56 A2 7E
13:58:23 01:58:23.443 Sent 7E A0 07 03 41 53 56 A2 7E
13:58:23 01:58:23.443 Received 7E A0 07 03 41 53 56 A2 7E
13:58:28 Data send failed. Try to resend 1/3
13:58:28 01:58:28.459 Sent 7E A0 07 03 41 53 56 A2 7E
13:58:28 01:58:28.469 Received 7E A0 07 03 41 53 56 A2 7E
13:58:33 Data send failed. Try to resend 2/3
13:58:33 01:58:33.484 Sent 7E A0 07 03 41 53 56 A2 7E
13:58:33 01:58:33.492 Received 7E A0 07 03 41 53 56 A2 7E
13:58:38 Data send failed. Try to resend 3/3
13:58:38 01:58:38.503 Sent 7E A0 07 03 41 53 56 A2 7E
13:58:38 01:58:38.513 Received 7E A0 07 03 41 53 56 A2 7E
13:58:43 Failed to receive reply from the device in given time.
13:58:43 01:58:43.531 Info Closing
13:58:43 01:58:43.563 Info Closed

Setting i have done

Manufacturer-> Indian Standard
Interface-> HDLC
Enable Logical Name Referencing
Authentication-> MR
Client Address-> 20
Password->ABCD0001
Address Type-> Default
Logical Server Address-> 0
Physical Server-> 1
Media-> Serial
Baudrate 9600, 8bit, Parity-> None , Hardware Flow Disable

Thanks In advance!

Kurumi

1 month 1 week ago

Hi,

The meter doesn't reply. There is only echo.

Your settings look correct, but because the meter is not reply, I believe that your baud rate is wrong or there is something wrong with the cables.

Try to connect with GXDLMSDirector. If you can, then the issues is with the cables.

BR,
Mikko