Contattore,interruttore automatico,inverter solare,contatore elettrico,batterie solari
Samwha EOCR-PFZ Motor Protection Relay
Confronto dei modelli: EOCRPFZ-WRDUH VS EOCRPFZ-H2DZ7W
Coding Rule for PFZ Series
`EOCRPFZ [CT Rating][Configurazione dei contatti][Display][Controllare il potere][Funzione][Comunicazione][Curva di viaggio][Terminal/Housing Type]`
- Model Suffix Breakdown
1) EOCRPFZ-WRDUH
W: Built-in CT range 0.5～100A (W-type CT)
R: Relay contact layout: Trip contact OL (1NA+1NC) + Alarm contact AL (1NO)
D: Display digitale
U: Control supply AC/DC 85～264V universal wide voltage
H: Integrated zero-sequence ZCT, earth fault protection supported
👉 No suffix Z = standard version; without special trip curve code, no Curve 7
2) EOCRPFZ-H2DZ7W
H: Built-in CT range 0.5～60A (H-type CT) ✅【Key Difference 1】
2: Configurazione dei contatti: Two independent changeover contact sets ✅【Key Difference 2】
D: Display digitale
Z: Built-in Modbus-RTU RS485 communication port ✅【Key Difference 3】
7: Special thermal protection curve (customized I²t overload & motor starting characteristic parameters, Curve No.7) ✅【Key Difference 4】
W: Alloggiamento / feed-through terminal type
⚠️ Nota importante:
EOCRPFZ-WRDUH has no Z code → no RS485 communication;
EOCRPFZ-H2DZ7W with Z suffix = factory-fitted Modbus communication.
- Main Comparison Table
| Elemento di confronto | EOCRPFZ-WRDUH | EOCRPFZ-H2DZ7W |
| Built-in CT Measuring Range | 0.5～100A | 0.5～60A |
| Controllare l'alimentazione | AC/DC 85～264V wide universal range | Typically AC100~240V (confirm upon order, wide voltage not guaranteed) |
| Output Relay Contacts | OL: 1NA+1NC; AL: 1NO | Two sets of changeover contacts (2×NO/NC), more contact terminals |
| Totale 3 contact points | ||
| Modbus RS485 Communication | ❌ Not supported | ✅ Standard onboard communication; allows PLC remote reading of current & codici di errore |
| Overload Protection Curve | Standard universal curve | Special No.7 trip curve (optimized for heavy-start loads: frantoi, air compressors etc.) |
| Protezione dai guasti a terra | Built-in ZCT, earth fault available | Built-in ZCT, earth fault available (stessa funzione) |
| 4～20mA Analog Output | Dual-channel 4–20mA output | Dual-channel 4–20mA output |
| Intercambiabilità diretta | ❌ Not plug-and-play | ❌ Not plug-and-play |
| Differences in measuring range, contact definition, communication and terminal layout |
- Selezione & On-site Replacement Guidelines
- Measuring Range Priority
EOCRPFZ-WRDUH max range 100A; EOCRPFZ-H2DZ7W max 60A.
Never use H2DZ7W if motor rated current exceeds 60A.
- Communication Requirement as Key Criterion
If remote current monitoring, fault signal acquisition or remote parameter setting via PLC is required → choose H2DZ7W (with Z communication).
Only local protection without upper system communication → EOCRPFZ-WRDUH is acceptable.
- Rewiring Required for Contact Circuits
Terminal assignments and contact numbers differ between the two models. Direct replacement will cause control circuit malfunction. Drawings and wiring must be rechecked and modified.
- Match Trip Curve with Load Type
No.7 curve version (suffisso 7) is preferred for crushers and heavy-duty long-start motors; standard curve WRDUH is sufficient for ordinary fans and water pumps.
- Brief Summary
- Campo di misura: WRDUH = 0.5–100A; H2DZ7W = 0.5–60A
- Comunicazione: H2DZ7W supports Modbus; WRDUH has no communication
- Contatti: H2DZ7W equipped with two changeover contact sets; WRDUH adopts standard 1OL+1AL contacts
- Protection curve: H2DZ7W uses special No.7 curve for heavy startup loads
- Alimentazione elettrica: WRDUH supports wide AC/DC 85~264V input for better compatibility
