mmi {CNAIM} R Documentation

## Maximum and Multiple Increment (MMI) Technique

### Description

This function returns a combined factor using a maximum and multiple increment (MMI) technique (cf. CNAIM, 2017. page 50, section 6.7.2). The function can be used to derive the health score factor for EHV and 132kV transformers. For deriviation of the health score factor for all other assets see `health_score_excl_ehv_132kv_tf`. To derive the health score factor for EHV and 132kV transformers one needs to use `mmi`() to derive the health score factor for the main transformer and for the tapchanger respectively. The constants `factor_divider_1`, `factor_divider_2` and `max_no_combined_factors` are all available in the lookup table 10 and 11 on page 53 and 54 in CNAIM (2017). For an in deph desciption see also section 6.8 on page 53 in CNAIM (2017). The `mmi`() can also be used in the derivation of observed and measured condition factors for all assets, using measured and observed input factors. The constants `factor_divider_1`, `factor_divider_2` and `max_no_combined_factors` can be found in table 13 on page 59 (observed condition factors) and in table 15 on page 63 (measured condition factors).

### Usage

```mmi(factors, factor_divider_1, factor_divider_2, max_no_combined_factors)
```

### Arguments

 `factors` Numeric vector. Factors to me combined. `factor_divider_1` Numeric. Constant that specifies the degree to which additional “good” or “bad” factors are able further drive the combined factor. `factor_divider_2` Numeric. Constant that specifies the degree to which additional “good” or “bad” factors are able further drive the combined factor. `max_no_combined_factors` Numeric. Specifies how many factors are able to simultaneously affect the combined factor.

### Value

Numeric. Combined factor.

### Source

DNO Common Network Asset Indices Methodology (CNAIM), Health & Criticality - Version 1.1, 2017: https://www.ofgem.gov.uk/system/files/docs/2017/05/dno_common_network_asset_indices_methodology_v1.1.pdf

### Examples

```mmi(factors = c(1,
1.5),
factor_divider_1 = 1.5,
factor_divider_2 = 1.5,
max_no_combined_factors = 1)
```

[Package CNAIM version 1.0.1 Index]