I.S. RTD / Resistance input CHARM specifications

Installation notes

This Intrinsically Safe CHARM requires the I.S. CHARM Terminal Block.
This CHARM can be configured for 2, 3, or 4-wire applications.

Specifications

Table: I.S.RTD Input CHARM specifications
Item	Specification
Channel type	RTD input
Sensor types	Refer to Table: I.S. RTD sensor type specifications
Sensor configuration	2, 3, or 4-wire
Full scale signal range	Selectable based on sensor. Refer to Table: I.S. RTD sensor type specifications
Accuracy over full temperature range	Depends upon the sensor type. Refer to the temperature drift specification in Table: I.S. RTD sensor type specifications
Repeatability	0.05% of span
Resolution	Depends upon the sensor type. Uses 24-bit A/D converter. Refer to the resolution specification in Table: I.S. RTD sensor type specifications
Calibration	None required
Sensor excitation current	0.5 mA in 2 and 4-wire configurations 0.25 mA in 3-wire configurations
DC50/60 Hz common mode rejection	90 dB typical
Channel isolation	Galvanically isolated according to EN 60079‐11, voltage peak value 375 VDC.
Open sensor detection	Yes
Input power requirements	+24 VDC input power: ±10% at 23 mA maximum
CHARM heat dissipation	0.60 W

Note

The accuracy and temperature drift values in the following table apply for a lead resistance of 0 Ω.

Table: I.S. RTD sensor type specifications
Sensor type	Operating range	25° reference accuracy			Temperature drift			Resolution
Sensor type	Operating range	4-wire	3-wire	2-wire	4-wire	3-wire	2-wire
Pt100	-200 to 850°C	0.50°C	1.91°C	1.20°C	0.015°C/°C	0.10°C/°C	0.05°C/°C	~0.02°C
Pt200	-200 to 850°C	0.40°C	1.34°C	0.74°C	0.014°C/°C	0.07°C/°C	0.03°C/°C	~0.02°C
Pt500	-200 to 850°C	0.34°C	1.00°C	0.47°C	0.014°C/°C	0.05°C/°C	0.02°C/°C	~0.02°C
Pt1000	-200 to 260°C	0.14°C	0.41°C	0.19°C	0.006°C/°C	0.02°C/°C	0.01°C/°C	~0.01°C
Ni100	-80 to 260 °C	0.18°C	0.85°C	0.62°C	0.003°C/°C	0.04°C/°C	0.03°C/°C	~0.01°C
Ni120	-80 to 260 °C	0.12°C	0.58°C	0.42°C	0.003°C/°C	0.03°C/°C	0.02°C/°C	~0.01°C
Ni200	-80 to 260 °C	0.11°C	0.47°C	0.33°C	0.003°C/°C	0.02°C/°C	0.02°C/°C	~0.01°C
Ni500	-80 to 260 °C	0.08°C	0.24°C	0.15°C	0.003°C/°C	0.01°C/°C	0.01°C/°C	~0.01°C
Ni1000	-80 to 140 °C	0.06°C	0.19°C	0.10°C	0.003°C/°C	0.01°C/°C	0.01°C/°C	~0.01°C
Cu10	-200 to 260°C	0.70°C	8.00°C⁽¹⁾	5.60°C	0.020°C/°C	0.42°C/°C⁽²⁾	0.29°C/°C	~0.01°C
Resistance/user defined (0-2 kΩ)⁽³⁾	0-100%	0.50 Ω	1.48 Ω	0.70 Ω	0.020 Ω/°C	0.08 Ω/°C	0.03 Ω/°C	~0.031 Ω

⁽¹⁾ 3-wire mode for Cu10 is disabled through the firmware

⁽²⁾ 3-wire mode for Cu10 is disabled through the firmware

⁽³⁾ (The Callendar-Van Dusen linearization equation can be used with user defined Pt RTDs. Refer to Recommended I/O Practices in DeltaV Books online for usage information.

Wiring diagrams

Figure: I.S. RTD / Resistance CHARM wiring diagram