---
title: "Which data types in the IEC 60870-5-104 protocol correspond to which ADSU types?"
slug: "which-data-types-in-the-iec-60870-5-104-protocol-correspond-to-which-adsu-types"
updated: 2026-05-27T13:26:26Z
published: 2026-05-27T13:26:26Z
canonical: "docs.insys-icom.com/which-data-types-in-the-iec-60870-5-104-protocol-correspond-to-which-adsu-types"
---

> ## Documentation Index
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# Which data types in the IEC 60870-5-104 protocol correspond to which ADSU types?

The following data types are available for data points:

| **-104 data type** | **Value range** | **Mapping behaviour** | **Supported ASDU types** |
| --- | --- | --- | --- |
| Singlepoint | 0/1 | Only digital data points can be mapped. If an analogue data point is mapped, the result is 0, if the analogue data point has the value 0; otherwise, the result is always 1. | 1 M_SP_NA_1 30 M_SP_TB_1 45 C_SC_NA_1 58 C_SC_TA_1 |
| Doublepoint | 0..3 | Unsigned integer values can be mapped here. Integer values that exceed the value range are interpreted as 3 (undefined). | 3 M_DP_NA_1 31 M_DP_TB_1 46 C_DC_NA_1 47 C_RC_NA_1 |
| Scaled value | -32768..32767 | Unsigned and signed integer values (16 bit) can be mapped here. | 11 M_ME_NB_1 35 M_ME_TE_1 49 C_SE_NB_1 62 C_SE_TB_1 |
| Normalized value | -1.0000..0.9999 | Float and double values within the value range permitted by the standard can be mapped here. Value range violations will not be handled. | 9 M_ME_NA_1 34 M_ME_TD_1 61 C_SE_TA_1 |
| Short value | Float 16 | Float and double values can be mapped here (a possible conversion will not affect the value, but only the accuracy of the value). | 13 M_ME_NC_1 36 M_ME_TF_1 50 C_SE_NC_1 |
| Protection event | 0..3 | Unsigned integer values can be mapped here. Integer values that exceed the value range are interpreted as 3 (undefined). | 38 M_EP_TD_1 |