The SIM100MLP is the first high-voltage isolation monitoring device for EV/HEVs capable of operating correctly even when the battery is active and experiencing large voltage variations, no variations, or even if the battery is not connected.
The SIM100MLP continuously monitors the isolation resistance between a vehicle’s IT (Isolated Terra) power system and chassis for deterioration of isolation and potentially dangerous levels of leakage current. The module detects resistive leakages and capacitively stored energy that could harm human operators.
Thanks to a proprietary, patented, and patent-pending advanced algorithm, the module can identify all leakage sources, including multiple symmetrical and asymmetrical faults occurring simultaneously, as well as resistive paths connecting the chassis to battery points with the same potential as the chassis. In the event of an isolated fault, the device determines the fault's location with respect to the battery's terminals.
In relation to the chassis (0 V), battery-connected voltage inputs can measure up to 1.1 kV (max; see ordering options for additional ranges). The unit functions across a broad temperature range of -40 °C to 105 °C and communicates over an isolated CAN 2.0B interface. The SIM100MLP was created as a part of systems that adhere to CFR 571.305, IEC 61557-A, UL 2231-1, UL 2231-2, ISO 6469-3:2011-12, and other relevant standards.
Highlights Applications
Usability
- Reports battery voltage
- Provides nonvolatile storage for the battery's maximum (design) voltage value, which is used to compute isolation resistance and stored energy
- Provides nonvolatile storage for calibration of the voltage measurements and other parameters
- Reports uncertainty for all measured and computed values
Performance
- Measures voltage at each battery terminal relative to the chassis
- Measures and reports the capacitance from each battery terminal to the chassis; computes and reports the energy stored by the total capacitance between the battery and chassis
- Initializes in less than six seconds
- Detects a change in the insulation value in less than 5 seconds
- Offers excellent protection against common-mode noise that could be present on the battery terminals
Safety
- Measures and reports modeled leakage resistances in accordance with the model modified by FMVSS §571.305, ISO6469-1, and other safety requirements
- Reports compute isolation resistance in Ω/V in accordance with safety standard requirements
- The device continuously checks its own connection to the chassis and the voltage sense lines’ connections to the battery terminals, indicating any weak connections in either scenario
- Offers an intrinsically leakage-safe excitation source that is galvanically separated
- Enough information is provided by a single CAN transmission to determine the system’s safety status
- The STATUS byte contains warning and fault alerts for low insulation resistance values
Benefits
- Measures isolation resistance accurately even when the battery is disconnected or the voltage dips below 15 V
- Improves system safety through constant monitoring and fault warnings
- Improves system performance through quick initialization and detection capabilities
- Offers reliable data storage and automatic calibration to ensure accuracy
Applications
Image Credit: Sensata Technologies BV
SIM100MLP™ Technical Specifications
Image Credit: Sensata Technologies BV
Operating Specifications. Source: Sensata Technologies BV
| Parameters |
Value |
| Power supply |
+4.8 to +53 V (variable, accommodating +5 V to +48 V power supplies) |
| Interface |
CAN 2.0B isolated, 120 Ω termination resistor (optional) |
| Voltage measurement range |
2 Channels: ±1100 (max) V/channel continuous, no signal clipping |
| Rating |
Automotive |
| Power consumption |
< 375 mW (+5 V power supply), < 475 mW (+48 V power supply) |
| Module operating temperature range |
-40 °C to 125 °C for electronics (-40 °C to 105 °C with connectors) |
Electrical Specifications. Source: Sensata Technologies BV
| Parameter |
Min |
Typical |
Max |
Units |
Conditions / Comments |
| Power and General |
| Electronics operating temperature range |
-40 |
|
125 |
°C |
|
| Connector temperature ratings |
-40 |
|
105 |
°C |
|
| Supply Voltage |
4.8 |
|
53 |
V |
|
| Supply Power |
|
|
500 |
mW |
|
| Start-up time |
|
6 |
|
s |
From the application of power and power supply stabilization to the availability of initial isolation values |
| Isolation Resistance Measurements |
| Isolation resistance monitoring range |
0 |
|
2.727 |
MΩ |
From each side of the battery to the chassis. (includes SIM100 resistances) |
| Isolation monitoring lines resistance |
|
2.726 |
|
MΩ |
This is the impedance imposed on the IT system by each of the two battery voltage monitoring lines and the maximum isolation resistance that can be measured |
| Isolation monitoring uncertainty |
|
±5 |
|
% |
For isolation resistance range of 100 kΩ to 500 kΩ, battery voltage above 15 V: The total measurement uncertainty includes the contribution by the noise and operations of the target system |
| Isolation values calculation period |
|
0.5 |
|
s |
The SIM100MLP calculates all reportable isolation values every 500 ms |
| Resistance value flagged as a short |
0 |
|
5 |
kΩ |
Reported isolation resistance value will be exactly 0 Ω/V |
| Voltage Measurement |
| Nominal full-scale voltage range |
±1520
±1109 |
±1552
±1132 |
|
V
V |
For SIM100MLP-xNx
For SIM100MLP-xMx |
| Voltage offset error |
-1 |
±0.2 |
+1 |
V |
VX = 0 V, applies over the full ambient operating temperature range, TA = -40 °C to 125 °C |
| Voltage gain error |
-1 |
±0.1 |
+1 |
% |
Over the full ambient operating temperature range. Calibration and typical |
| Voltage noise error |
|
200 |
|
mVRMS |
1 Hz reporting rate |
| Voltage measurement resolution |
|
1 |
|
V |
Minimum reportable voltage change |
| Permitted battery voltage |
0
0 |
|
1500
1109 |
V
V |
For SIM100MLP-xNx
For SIM100MLP-xKx
If the battery voltage is under 15 V, only parallel resistance and capacitance will be accurate |
| Capacitance Measurement |
| Capacitance monitoring range |
0.1 |
1 |
2 |
μF |
Capacitance from each terminal of the battery to chassis. A 100 nF capacitance (minimum) is required for normal functioning |
| Capacitance monitoring uncertainty |
|
±15 |
|
% |
200 nF to 2 μF, when battery voltage has at least 2 V periodic variations |
| Capacitance measurement resolution |
|
1 |
|
nF |
|
| Temperature Measurement |
| Absolute temperature measurement error |
-5 |
±0.5 |
+5 |
°C |
Built-in temperature sensor |
| Temperature measurement resolution |
|
|
10 |
m°C |
Practical temperature measurement granularity |
| Noise Immunity of Measurements |
| Common mode voltage on the battery terminals |
20 |
|
|
VPK-PK |
No observable effect on isolation resistance value; measured with square and triangular wave test signals at 1 kHz, 10 kHz and 30 kHz |
| Differential mode voltage on the battery terminals (battery voltage variations) |
|
100 |
|
VPK-PK |
No observable effect on isolation resistance value; tested with a battery-voltage driving profile that has multiple instantaneous voltage changes up to ±100 V and overall slow battery voltage fluctuation from 330 V to 125 V and back to 330 V |
| Test voltage |
|
|
3 |
kVDC |
CAN interface to chassis, 1 min. duration |
ESD
tolerance |
|
|
25 |
kV |
Air discharge to VX1/VX2 terminals; CAN connector’s signals and/or Chassis connector signals have continuity to reference GND of the ESD tester |
| |
|
±15 k |
kV |
Contact discharge to VX1/VX2 terminals, same conditions as above |
Communication. Source: Sensata Technologies BV
| Interface |
Spec |
Speed |
Termination |
| CAN |
2.0B |
500 or 250 kbit/s |
120 Ω termination resistor optional |
Connectors. Source: Sensata Technologies BV
| Interface |
Manufacturer |
Position |
Part Number |
Description |
| CAN & power on board |
Molex |
4 |
705510038 |
P1: 4 pos. right angle header, shrouded connector (2.54 mm), through hole tin |
| Can & power mating con. |
Molex |
4 |
50579404
50579704
(with TPA) |
Use appropriate crimp contacts (available for AWG 22, 24 and 26) |
| Voltage sensing on board |
Molex |
2 |
705510036 |
J1, J3, J4: MINIFIT JR HDR 02P 94V-030AU |
| Voltage sensing mating con. |
Molex |
2 |
50579402
50579702
(with TPA) |
MINIFIT JR RCPT DR SIDETABS 2 CKT 94V-0. Crimp contacts available for AWG 18 to 28 |
Molex connections (part numbers 705510036 and 705510038) are used with the SIM100MLP.